diff --git a/Source/Core/Common/ArmEmitter.cpp b/Source/Core/Common/ArmEmitter.cpp
index ccd05d4c459..aeaba58997d 100644
--- a/Source/Core/Common/ArmEmitter.cpp
+++ b/Source/Core/Common/ArmEmitter.cpp
@@ -916,7 +916,7 @@ u32 EncodeVm(ARMReg Vm)
 }
 
 // Double/single, Neon
-extern const VFPEnc VFPOps[16][2] = {
+const VFPEnc VFPOps[16][2] = {
 	{{0xE0, 0xA0}, {  -1,   -1}}, // 0: VMLA
 	{{0xE1, 0xA4}, {  -1,   -1}}, // 1: VNMLA
 	{{0xE0, 0xA4}, {  -1,   -1}}, // 2: VMLS
diff --git a/Source/Core/Common/MsgHandler.h b/Source/Core/Common/MsgHandler.h
index 36032fe09a7..079e960f833 100644
--- a/Source/Core/Common/MsgHandler.h
+++ b/Source/Core/Common/MsgHandler.h
@@ -22,7 +22,7 @@ typedef std::string (*StringTranslator)(const char* text);
 void RegisterMsgAlertHandler(MsgAlertHandler handler);
 void RegisterStringTranslator(StringTranslator translator);
 
-extern bool MsgAlert(bool yes_no, int Style, const char* format, ...)
+bool MsgAlert(bool yes_no, int Style, const char* format, ...)
 #ifdef __GNUC__
 	__attribute__((format(printf, 3, 4)))
 #endif
diff --git a/Source/Core/Core/HW/DSPHLE/UCodes/UCodes.h b/Source/Core/Core/HW/DSPHLE/UCodes/UCodes.h
index ae007a61be1..f952cb5b151 100644
--- a/Source/Core/Core/HW/DSPHLE/UCodes/UCodes.h
+++ b/Source/Core/Core/HW/DSPHLE/UCodes/UCodes.h
@@ -136,4 +136,4 @@ private:
 	bool m_needs_resume_mail;
 };
 
-extern UCodeInterface* UCodeFactory(u32 crc, DSPHLE *dsphle, bool wii);
+UCodeInterface* UCodeFactory(u32 crc, DSPHLE *dsphle, bool wii);
diff --git a/Source/Core/Core/HW/EXI_Device.h b/Source/Core/Core/HW/EXI_Device.h
index 01a77b9af80..58b3a426cd0 100644
--- a/Source/Core/Core/HW/EXI_Device.h
+++ b/Source/Core/Core/HW/EXI_Device.h
@@ -53,4 +53,4 @@ public:
 	TEXIDevices m_deviceType;
 };
 
-extern IEXIDevice* EXIDevice_Create(const TEXIDevices device_type, const int channel_num);
+IEXIDevice* EXIDevice_Create(const TEXIDevices device_type, const int channel_num);
diff --git a/Source/Core/Core/HW/Memmap.h b/Source/Core/Core/HW/Memmap.h
index c40d0b2e825..ef0032490ff 100644
--- a/Source/Core/Core/HW/Memmap.h
+++ b/Source/Core/Core/HW/Memmap.h
@@ -47,7 +47,6 @@ extern u8 *m_pEXRAM;
 extern u8 *m_pL1Cache;
 extern u8 *m_pVirtualFakeVMEM;
 extern u8 *m_pFakeVMEM;
-extern bool bFakeVMEM;
 
 enum
 {
diff --git a/Source/Core/Core/HW/MemmapFunctions.cpp b/Source/Core/Core/HW/MemmapFunctions.cpp
index 828f576c674..1faaa6c3d40 100644
--- a/Source/Core/Core/HW/MemmapFunctions.cpp
+++ b/Source/Core/Core/HW/MemmapFunctions.cpp
@@ -22,6 +22,7 @@
 #include "Core/HW/GPFifo.h"
 #include "Core/HW/Memmap.h"
 #include "Core/HW/MMIO.h"
+#include "Core/PowerPC/JitInterface.h"
 #include "Core/PowerPC/PowerPC.h"
 
 #include "VideoCommon/VideoBackendBase.h"
@@ -53,15 +54,6 @@ GXPeekZ
 // From Memmap.cpp
 // ----------------
 
-// Pointers to low memory
-extern u8 *m_pFakeVMEM;
-extern u8 *m_pEXRAM;  // Wii
-extern u8 *m_pEFB;
-
-// Init
-extern bool m_IsInitialized;
-extern bool bFakeVMEM;
-
 // Overloaded byteswap functions, for use within the templated functions below.
 inline u8 bswap(u8 val)   {return val;}
 inline u16 bswap(u16 val) {return Common::swap16(val);}
diff --git a/Source/Core/Core/HW/SI_Device.h b/Source/Core/Core/HW/SI_Device.h
index 5c819dccc20..66f85fb53ce 100644
--- a/Source/Core/Core/HW/SI_Device.h
+++ b/Source/Core/Core/HW/SI_Device.h
@@ -95,4 +95,4 @@ public:
 	}
 };
 
-extern ISIDevice* SIDevice_Create(const SIDevices device, const int port_number);
+ISIDevice* SIDevice_Create(const SIDevices device, const int port_number);
diff --git a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.cpp b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.cpp
index 68a5689f34e..b995111a243 100644
--- a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.cpp
+++ b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.cpp
@@ -50,8 +50,6 @@ typedef struct pollfd pollfd_t;
 #include <errno.h>
 #endif
 
-extern std::queue<std::pair<u32,std::string> > g_ReplyQueueLater;
-
 // **********************************************************************************
 // Handle /dev/net/kd/request requests
 CWII_IPC_HLE_Device_net_kd_request::CWII_IPC_HLE_Device_net_kd_request(u32 _DeviceID, const std::string& _rDeviceName)
diff --git a/Source/Core/Core/PowerPC/Jit64/Jit.cpp b/Source/Core/Core/PowerPC/Jit64/Jit.cpp
index 7dac00d4354..837b3c4be9f 100644
--- a/Source/Core/Core/PowerPC/Jit64/Jit.cpp
+++ b/Source/Core/Core/PowerPC/Jit64/Jit.cpp
@@ -142,11 +142,6 @@ ps_adds1
 
 static int CODE_SIZE = 1024*1024*32;
 
-namespace CPUCompare
-{
-	extern u32 m_BlockStart;
-}
-
 void Jit64::Init()
 {
 	jo.optimizeStack = true;
diff --git a/Source/Core/Core/PowerPC/Jit64IL/JitIL.cpp b/Source/Core/Core/PowerPC/Jit64IL/JitIL.cpp
index cbba470354f..a3cb619f620 100644
--- a/Source/Core/Core/PowerPC/Jit64IL/JitIL.cpp
+++ b/Source/Core/Core/PowerPC/Jit64IL/JitIL.cpp
@@ -234,11 +234,6 @@ namespace JitILProfiler
 
 static int CODE_SIZE = 1024*1024*32;
 
-namespace CPUCompare
-{
-	extern u32 m_BlockStart;
-}
-
 void JitIL::Init()
 {
 	jo.optimizeStack = true;
diff --git a/Source/Core/Core/PowerPC/JitArm32/Jit.cpp b/Source/Core/Core/PowerPC/JitArm32/Jit.cpp
index 5d814cedd67..afe4d490cc3 100644
--- a/Source/Core/Core/PowerPC/JitArm32/Jit.cpp
+++ b/Source/Core/Core/PowerPC/JitArm32/Jit.cpp
@@ -26,10 +26,6 @@ using namespace ArmGen;
 using namespace PowerPC;
 
 static int CODE_SIZE = 1024*1024*32;
-namespace CPUCompare
-{
-	extern u32 m_BlockStart;
-}
 
 void JitArm::Init()
 {
diff --git a/Source/Core/Core/PowerPC/JitArm32/JitArm_Integer.cpp b/Source/Core/Core/PowerPC/JitArm32/JitArm_Integer.cpp
index 2708cd8ee19..5f47aefb34d 100644
--- a/Source/Core/Core/PowerPC/JitArm32/JitArm_Integer.cpp
+++ b/Source/Core/Core/PowerPC/JitArm32/JitArm_Integer.cpp
@@ -14,8 +14,6 @@
 #include "Core/PowerPC/JitArm32/JitAsm.h"
 #include "Core/PowerPC/JitArm32/JitRegCache.h"
 
-extern u32 Helper_Mask(u8 mb, u8 me);
-
 // Assumes that Sign and Zero flags were set by the last operation. Preserves all flags and registers.
 // Jit64 ComputerRC is signed
 // JIT64 GenerateRC is unsigned
diff --git a/Source/Core/Core/PowerPC/JitArmIL/JitIL.cpp b/Source/Core/Core/PowerPC/JitArmIL/JitIL.cpp
index f47b6f2536f..e1a711e4322 100644
--- a/Source/Core/Core/PowerPC/JitArmIL/JitIL.cpp
+++ b/Source/Core/Core/PowerPC/JitArmIL/JitIL.cpp
@@ -25,10 +25,7 @@ using namespace ArmGen;
 using namespace PowerPC;
 
 static int CODE_SIZE = 1024*1024*32;
-namespace CPUCompare
-{
-	extern u32 m_BlockStart;
-}
+
 void JitArmIL::Init()
 {
 	AllocCodeSpace(CODE_SIZE);
diff --git a/Source/Core/Core/PowerPC/JitCommon/JitBackpatch.cpp b/Source/Core/Core/PowerPC/JitCommon/JitBackpatch.cpp
index 53bc48cf9ca..6e987009d6c 100644
--- a/Source/Core/Core/PowerPC/JitCommon/JitBackpatch.cpp
+++ b/Source/Core/Core/PowerPC/JitCommon/JitBackpatch.cpp
@@ -19,8 +19,6 @@
 
 using namespace Gen;
 
-extern u8 *trampolineCodePtr;
-
 #if _M_X86_64
 static void BackPatchError(const std::string &text, u8 *codePtr, u32 emAddress) {
 	u64 code_addr = (u64)codePtr;
diff --git a/Source/Core/DolphinWX/CheatsWindow.cpp b/Source/Core/DolphinWX/CheatsWindow.cpp
index b0c84c29c74..9fc6fb94e74 100644
--- a/Source/Core/DolphinWX/CheatsWindow.cpp
+++ b/Source/Core/DolphinWX/CheatsWindow.cpp
@@ -44,13 +44,12 @@
 #include "DolphinWX/Frame.h"
 #include "DolphinWX/GeckoCodeDiag.h"
 #include "DolphinWX/ISOProperties.h"
+#include "DolphinWX/Main.h"
 #include "DolphinWX/WxUtils.h"
 
 class wxWindow;
 
 #define MAX_CHEAT_SEARCH_RESULTS_DISPLAY  256
-extern std::vector<ActionReplay::ARCode> arCodes;
-extern CFrame* main_frame;
 
 // meh
 static wxCheatsWindow *g_cheat_window;
diff --git a/Source/Core/DolphinWX/ConfigMain.cpp b/Source/Core/DolphinWX/ConfigMain.cpp
index 9208b70b08f..3a061f5e6cf 100644
--- a/Source/Core/DolphinWX/ConfigMain.cpp
+++ b/Source/Core/DolphinWX/ConfigMain.cpp
@@ -71,8 +71,6 @@ const CPUCore CPUCores[] = {
 #endif
 };
 
-extern CFrame* main_frame;
-
 // keep these in sync with CConfigMain::InitializeGUILists
 static const wxLanguage langIds[] =
 {
diff --git a/Source/Core/DolphinWX/Debugger/DebuggerPanel.cpp b/Source/Core/DolphinWX/Debugger/DebuggerPanel.cpp
index fa09024ef33..edee4fac647 100644
--- a/Source/Core/DolphinWX/Debugger/DebuggerPanel.cpp
+++ b/Source/Core/DolphinWX/Debugger/DebuggerPanel.cpp
@@ -43,12 +43,6 @@ BEGIN_EVENT_TABLE(GFXDebuggerPanel, wxPanel)
 	EVT_BUTTON(ID_CLEAR_PIXEL_SHADER_CACHE,GFXDebuggerPanel::OnClearPixelShaderCacheButton)
 END_EVENT_TABLE()
 
-// From VideoCommon
-extern GFXDebuggerBase *g_pdebugger;
-extern volatile bool GFXDebuggerPauseFlag;
-extern volatile PauseEvent GFXDebuggerToPauseAtNext;
-extern volatile int GFXDebuggerEventToPauseCount;
-
 GFXDebuggerPanel::GFXDebuggerPanel(wxWindow *parent, wxWindowID id, const wxPoint &position,
 									const wxSize& size, long style, const wxString &title)
 	: wxPanel(parent, id, position, size, style, title)
diff --git a/Source/Core/DolphinWX/Frame.cpp b/Source/Core/DolphinWX/Frame.cpp
index b258c2f2afb..d0f379b78ae 100644
--- a/Source/Core/DolphinWX/Frame.cpp
+++ b/Source/Core/DolphinWX/Frame.cpp
@@ -61,6 +61,7 @@
 #include "DolphinWX/GameListCtrl.h"
 #include "DolphinWX/Globals.h"
 #include "DolphinWX/LogWindow.h"
+#include "DolphinWX/Main.h"
 #include "DolphinWX/TASInputDlg.h"
 #include "DolphinWX/WxUtils.h"
 #include "DolphinWX/Debugger/CodeWindow.h"
@@ -88,9 +89,6 @@ HWND MSWGetParent_(HWND Parent)
 // ---------------
 // The CPanel class to receive MSWWindowProc messages from the video backend.
 
-extern CFrame* main_frame;
-
-
 BEGIN_EVENT_TABLE(CPanel, wxPanel)
 END_EVENT_TABLE()
 
diff --git a/Source/Core/DolphinWX/GameListCtrl.cpp b/Source/Core/DolphinWX/GameListCtrl.cpp
index 33eb8cf3f7f..a517b3256a1 100644
--- a/Source/Core/DolphinWX/GameListCtrl.cpp
+++ b/Source/Core/DolphinWX/GameListCtrl.cpp
@@ -84,8 +84,6 @@ size_t CGameListCtrl::m_numberItem = 0;
 std::string CGameListCtrl::m_currentFilename;
 static bool sorted = false;
 
-extern CFrame* main_frame;
-
 static int CompareGameListItems(const GameListItem* iso1, const GameListItem* iso2,
                                 long sortData = CGameListCtrl::COLUMN_TITLE)
 {
diff --git a/Source/Core/DolphinWX/NetWindow.cpp b/Source/Core/DolphinWX/NetWindow.cpp
index 495f6c00e70..391ce0ff9ce 100644
--- a/Source/Core/DolphinWX/NetWindow.cpp
+++ b/Source/Core/DolphinWX/NetWindow.cpp
@@ -42,6 +42,7 @@
 #include "DolphinWX/Frame.h"
 #include "DolphinWX/GameListCtrl.h"
 #include "DolphinWX/ISOFile.h"
+#include "DolphinWX/Main.h"
 #include "DolphinWX/NetWindow.h"
 #include "DolphinWX/WxUtils.h"
 
@@ -56,7 +57,6 @@ END_EVENT_TABLE()
 
 static NetPlayServer* netplay_server = nullptr;
 static NetPlayClient* netplay_client = nullptr;
-extern CFrame* main_frame;
 NetPlayDiag *NetPlayDiag::npd = nullptr;
 
 static std::string BuildGameName(const GameListItem& game)
diff --git a/Source/Core/DolphinWX/VideoConfigDiag.cpp b/Source/Core/DolphinWX/VideoConfigDiag.cpp
index 6b74a54f66f..00fab2bb6a3 100644
--- a/Source/Core/DolphinWX/VideoConfigDiag.cpp
+++ b/Source/Core/DolphinWX/VideoConfigDiag.cpp
@@ -28,6 +28,7 @@
 #include "Core/Core.h"
 #include "Core/CoreParameter.h"
 #include "DolphinWX/Frame.h"
+#include "DolphinWX/Main.h"
 #include "DolphinWX/VideoConfigDiag.h"
 #include "DolphinWX/WxUtils.h"
 #include "VideoCommon/VideoBackendBase.h"
@@ -37,8 +38,6 @@
 #include <ApplicationServices/ApplicationServices.h>
 #endif
 
-extern CFrame* main_frame;
-
 // template instantiation
 template class BoolSetting<wxCheckBox>;
 template class BoolSetting<wxRadioButton>;
diff --git a/Source/Core/VideoBackends/D3D/PixelShaderCache.cpp b/Source/Core/VideoBackends/D3D/PixelShaderCache.cpp
index d4fa12d44ae..22e035c5a0d 100644
--- a/Source/Core/VideoBackends/D3D/PixelShaderCache.cpp
+++ b/Source/Core/VideoBackends/D3D/PixelShaderCache.cpp
@@ -21,9 +21,6 @@
 #include "VideoCommon/Statistics.h"
 #include "VideoCommon/VideoConfig.h"
 
-
-extern int frameCount;
-
 namespace DX11
 {
 
diff --git a/Source/Core/VideoBackends/D3D/VertexManager.cpp b/Source/Core/VideoBackends/D3D/VertexManager.cpp
index 00e32ed871b..6ae5f17a3f4 100644
--- a/Source/Core/VideoBackends/D3D/VertexManager.cpp
+++ b/Source/Core/VideoBackends/D3D/VertexManager.cpp
@@ -16,12 +16,10 @@
 #include "VideoCommon/RenderBase.h"
 #include "VideoCommon/Statistics.h"
 #include "VideoCommon/TextureCacheBase.h"
+#include "VideoCommon/VertexLoader.h"
 #include "VideoCommon/VertexShaderManager.h"
 #include "VideoCommon/VideoConfig.h"
 
-// internal state for loading vertices
-extern NativeVertexFormat *g_nativeVertexFmt;
-
 namespace DX11
 {
 
diff --git a/Source/Core/VideoBackends/OGL/Render.h b/Source/Core/VideoBackends/OGL/Render.h
index 2ccc00ac0b5..c51be20d86f 100644
--- a/Source/Core/VideoBackends/OGL/Render.h
+++ b/Source/Core/VideoBackends/OGL/Render.h
@@ -17,7 +17,7 @@ enum GLSL_VERSION {
 };
 
 // ogl-only config, so not in VideoConfig.h
-extern struct VideoConfig {
+struct VideoConfig {
 	bool bSupportsGLSLCache;
 	bool bSupportsGLPinnedMemory;
 	bool bSupportsGLSync;
@@ -35,7 +35,8 @@ extern struct VideoConfig {
 	const char* glsl_version;
 
 	s32 max_samples;
-} g_ogl_config;
+};
+extern VideoConfig g_ogl_config;
 
 class Renderer : public ::Renderer
 {
diff --git a/Source/Core/VideoBackends/OGL/VertexManager.cpp b/Source/Core/VideoBackends/OGL/VertexManager.cpp
index 1f3194a6fdc..0ac59041b7d 100644
--- a/Source/Core/VideoBackends/OGL/VertexManager.cpp
+++ b/Source/Core/VideoBackends/OGL/VertexManager.cpp
@@ -29,9 +29,6 @@
 #include "VideoCommon/VertexShaderManager.h"
 #include "VideoCommon/VideoConfig.h"
 
-// internal state for loading vertices
-extern NativeVertexFormat *g_nativeVertexFmt;
-
 namespace OGL
 {
 //This are the initially requested size for the buffers expressed in bytes
diff --git a/Source/Core/VideoBackends/Software/DebugUtil.cpp b/Source/Core/VideoBackends/Software/DebugUtil.cpp
index bd59779e869..5998b10b091 100644
--- a/Source/Core/VideoBackends/Software/DebugUtil.cpp
+++ b/Source/Core/VideoBackends/Software/DebugUtil.cpp
@@ -15,6 +15,7 @@
 #include "VideoBackends/Software/SWVideoConfig.h"
 #include "VideoBackends/Software/TextureSampler.h"
 
+#include "VideoCommon/Fifo.h"
 #include "VideoCommon/ImageWrite.h"
 
 
diff --git a/Source/Core/VideoBackends/Software/EfbCopy.cpp b/Source/Core/VideoBackends/Software/EfbCopy.cpp
index 9629670a3f5..77f141d60a3 100644
--- a/Source/Core/VideoBackends/Software/EfbCopy.cpp
+++ b/Source/Core/VideoBackends/Software/EfbCopy.cpp
@@ -14,6 +14,7 @@
 #include "VideoBackends/Software/SWStatistics.h"
 #include "VideoBackends/Software/SWVideoConfig.h"
 #include "VideoBackends/Software/TextureEncoder.h"
+#include "VideoCommon/Fifo.h"
 
 static const float s_gammaLUT[] =
 {
diff --git a/Source/Core/VideoBackends/Software/OpcodeDecoder.cpp b/Source/Core/VideoBackends/Software/OpcodeDecoder.cpp
index 524a960d3e3..33863c892c1 100644
--- a/Source/Core/VideoBackends/Software/OpcodeDecoder.cpp
+++ b/Source/Core/VideoBackends/Software/OpcodeDecoder.cpp
@@ -14,6 +14,7 @@
 #include "VideoBackends/Software/SWVideoConfig.h"
 #include "VideoBackends/Software/XFMemLoader.h"
 #include "VideoCommon/DataReader.h"
+#include "VideoCommon/Fifo.h"
 
 typedef void (*DecodingFunction)(u32);
 
diff --git a/Source/Core/VideoBackends/Software/SWCommandProcessor.cpp b/Source/Core/VideoBackends/Software/SWCommandProcessor.cpp
index 1a2dcc0cbf6..3b80b9ddbfa 100644
--- a/Source/Core/VideoBackends/Software/SWCommandProcessor.cpp
+++ b/Source/Core/VideoBackends/Software/SWCommandProcessor.cpp
@@ -20,6 +20,8 @@
 #include "VideoBackends/Software/SWCommandProcessor.h"
 #include "VideoBackends/Software/VideoBackend.h"
 
+#include "VideoCommon/DataReader.h"
+#include "VideoCommon/Fifo.h"
 
 namespace SWCommandProcessor
 {
diff --git a/Source/Core/VideoBackends/Software/SWCommandProcessor.h b/Source/Core/VideoBackends/Software/SWCommandProcessor.h
index dbedc101ac6..e30eccfec57 100644
--- a/Source/Core/VideoBackends/Software/SWCommandProcessor.h
+++ b/Source/Core/VideoBackends/Software/SWCommandProcessor.h
@@ -11,9 +11,6 @@
 class PointerWrap;
 namespace MMIO { class Mapping; }
 
-extern volatile bool g_bSkipCurrentFrame;
-extern u8* g_pVideoData;
-
 namespace SWCommandProcessor
 {
 	using UCPStatusReg = CommandProcessor::UCPStatusReg;
diff --git a/Source/Core/VideoBackends/Software/SWVertexLoader.cpp b/Source/Core/VideoBackends/Software/SWVertexLoader.cpp
index f0cc09e3d28..52af0ae1a1c 100644
--- a/Source/Core/VideoBackends/Software/SWVertexLoader.cpp
+++ b/Source/Core/VideoBackends/Software/SWVertexLoader.cpp
@@ -12,20 +12,13 @@
 #include "VideoBackends/Software/XFMemLoader.h"
 
 #include "VideoCommon/DataReader.h"
+#include "VideoCommon/VertexLoader.h"
 #include "VideoCommon/VertexLoader_Color.h"
 #include "VideoCommon/VertexLoader_Normal.h"
 #include "VideoCommon/VertexLoader_Position.h"
 #include "VideoCommon/VertexLoader_TextCoord.h"
 #include "VideoCommon/VertexManagerBase.h"
 
-// Vertex loaders read these
-extern int tcIndex;
-extern int colIndex;
-extern int colElements[2];
-extern float posScale;
-extern float tcScale[8];
-
-
 SWVertexLoader::SWVertexLoader() :
 	m_VertexSize(0),
 	m_NumAttributeLoaders(0)
diff --git a/Source/Core/VideoBackends/Software/SWmain.cpp b/Source/Core/VideoBackends/Software/SWmain.cpp
index 8abfa81c654..13bd20d154f 100644
--- a/Source/Core/VideoBackends/Software/SWmain.cpp
+++ b/Source/Core/VideoBackends/Software/SWmain.cpp
@@ -35,6 +35,7 @@
 #include "VideoBackends/Software/VideoConfigDialog.h"
 #endif // HAVE_WX
 
+#include "VideoCommon/Fifo.h"
 #include "VideoCommon/OnScreenDisplay.h"
 #include "VideoCommon/PixelEngine.h"
 #include "VideoCommon/XFMemory.h"
diff --git a/Source/Core/VideoCommon/BPStructs.cpp b/Source/Core/VideoCommon/BPStructs.cpp
index e9fdf1f83c0..6ba663b75d8 100644
--- a/Source/Core/VideoCommon/BPStructs.cpp
+++ b/Source/Core/VideoCommon/BPStructs.cpp
@@ -11,6 +11,7 @@
 
 #include "VideoCommon/BPFunctions.h"
 #include "VideoCommon/BPStructs.h"
+#include "VideoCommon/Fifo.h"
 #include "VideoCommon/PerfQueryBase.h"
 #include "VideoCommon/PixelEngine.h"
 #include "VideoCommon/PixelShaderManager.h"
@@ -24,8 +25,6 @@
 
 using namespace BPFunctions;
 
-extern volatile bool g_bSkipCurrentFrame;
-
 static const float s_gammaLUT[] =
 {
 	1.0f,
diff --git a/Source/Core/VideoCommon/Debugger.cpp b/Source/Core/VideoCommon/Debugger.cpp
index c5ca50f1329..b5dcca740f0 100644
--- a/Source/Core/VideoCommon/Debugger.cpp
+++ b/Source/Core/VideoCommon/Debugger.cpp
@@ -15,7 +15,6 @@
 #include "VideoCommon/VideoConfig.h"
 
 //void UpdateFPSDisplay(const char *text);
-extern NativeVertexFormat *g_nativeVertexFmt;
 
 GFXDebuggerBase *g_pdebugger = nullptr;
 volatile bool GFXDebuggerPauseFlag = false; // if true, the GFX thread will be spin locked until it's false again
diff --git a/Source/Core/VideoCommon/Fifo.cpp b/Source/Core/VideoCommon/Fifo.cpp
index 2886498acb2..3460b259560 100644
--- a/Source/Core/VideoCommon/Fifo.cpp
+++ b/Source/Core/VideoCommon/Fifo.cpp
@@ -13,13 +13,13 @@
 #include "Core/HW/Memmap.h"
 
 #include "VideoCommon/CommandProcessor.h"
+#include "VideoCommon/DataReader.h"
 #include "VideoCommon/Fifo.h"
 #include "VideoCommon/OpcodeDecoding.h"
 #include "VideoCommon/PixelEngine.h"
 #include "VideoCommon/VideoConfig.h"
 
 volatile bool g_bSkipCurrentFrame = false;
-extern u8* g_pVideoData;
 
 namespace
 {
diff --git a/Source/Core/VideoCommon/TextureCacheBase.cpp b/Source/Core/VideoCommon/TextureCacheBase.cpp
index 33d6b3b919c..d43e209a72f 100644
--- a/Source/Core/VideoCommon/TextureCacheBase.cpp
+++ b/Source/Core/VideoCommon/TextureCacheBase.cpp
@@ -19,9 +19,6 @@
 #include "VideoCommon/TextureCacheBase.h"
 #include "VideoCommon/VideoConfig.h"
 
-// ugly
-extern int frameCount;
-
 enum
 {
 	TEXTURE_KILL_THRESHOLD = 200,
diff --git a/Source/Core/VideoCommon/TextureDecoder.h b/Source/Core/VideoCommon/TextureDecoder.h
index 284b992f457..45925f7aaf4 100644
--- a/Source/Core/VideoCommon/TextureDecoder.h
+++ b/Source/Core/VideoCommon/TextureDecoder.h
@@ -52,6 +52,10 @@ enum TextureFormat
 	GX_CTF_Z16L  = 0xC | _GX_TF_ZTF | _GX_TF_CTF,
 };
 
+extern const char* texfmt[];
+extern const unsigned char sfont_map[];
+extern const unsigned char sfont_raw[][9*10];
+
 int TexDecoder_GetTexelSizeInNibbles(int format);
 int TexDecoder_GetTextureSizeInBytes(int width, int height, int format);
 int TexDecoder_GetBlockWidthInTexels(u32 format);
diff --git a/Source/Core/VideoCommon/TextureDecoder_Generic.cpp b/Source/Core/VideoCommon/TextureDecoder_Generic.cpp
index e945010f682..c9549b4688e 100644
--- a/Source/Core/VideoCommon/TextureDecoder_Generic.cpp
+++ b/Source/Core/VideoCommon/TextureDecoder_Generic.cpp
@@ -15,10 +15,6 @@
 bool TexFmt_Overlay_Enable=false;
 bool TexFmt_Overlay_Center=false;
 
-extern const char* texfmt[];
-extern const unsigned char sfont_map[];
-extern const unsigned char sfont_raw[][9*10];
-
 // TRAM
 // STATE_TO_SAVE
  GC_ALIGNED16(u8 texMem[TMEM_SIZE]);
diff --git a/Source/Core/VideoCommon/TextureDecoder_x64.cpp b/Source/Core/VideoCommon/TextureDecoder_x64.cpp
index 63e5207c82c..a0ec1bba05b 100644
--- a/Source/Core/VideoCommon/TextureDecoder_x64.cpp
+++ b/Source/Core/VideoCommon/TextureDecoder_x64.cpp
@@ -35,10 +35,6 @@
 static bool TexFmt_Overlay_Enable=false;
 static bool TexFmt_Overlay_Center=false;
 
-extern const char* texfmt[];
-extern const unsigned char sfont_map[];
-extern const unsigned char sfont_raw[][9*10];
-
 // TRAM
 // STATE_TO_SAVE
  GC_ALIGNED16(u8 texMem[TMEM_SIZE]);
diff --git a/Source/Core/VideoCommon/VertexLoader_Color.cpp b/Source/Core/VideoCommon/VertexLoader_Color.cpp
index 03fee032928..8ffed47bac9 100644
--- a/Source/Core/VideoCommon/VertexLoader_Color.cpp
+++ b/Source/Core/VideoCommon/VertexLoader_Color.cpp
@@ -16,10 +16,6 @@
 #define ASHIFT 24
 #define AMASK 0xFF000000
 
-extern int colIndex;
-extern int colElements[2];
-
-
 __forceinline void _SetCol(u32 val)
 {
 	DataWrite(val);
diff --git a/Source/Core/VideoCommon/VertexLoader_Position.cpp b/Source/Core/VideoCommon/VertexLoader_Position.cpp
index f95ef665bfe..9554adccd5c 100644
--- a/Source/Core/VideoCommon/VertexLoader_Position.cpp
+++ b/Source/Core/VideoCommon/VertexLoader_Position.cpp
@@ -12,9 +12,6 @@
 #include "VideoCommon/VertexManagerBase.h"
 #include "VideoCommon/VideoCommon.h"
 
-extern float posScale;
-extern TVtxAttr *pVtxAttr;
-
 // Thoughts on the implementation of a vertex loader compiler.
 // s_pCurBufferPointer should definitely be in a register.
 // Could load the position scale factor in XMM7, for example.
diff --git a/Source/Core/VideoCommon/VertexLoader_TextCoord.cpp b/Source/Core/VideoCommon/VertexLoader_TextCoord.cpp
index 032ef1d90f4..5b47b4f3abf 100644
--- a/Source/Core/VideoCommon/VertexLoader_TextCoord.cpp
+++ b/Source/Core/VideoCommon/VertexLoader_TextCoord.cpp
@@ -34,9 +34,6 @@ __forceinline void LOG_TEX<2>()
 	// PRIM_LOG("tex: %f %f, ", ((float*)VertexManager::s_pCurBufferPointer)[-2], ((float*)VertexManager::s_pCurBufferPointer)[-1]);
 }
 
-extern int tcIndex;
-extern float tcScale[8];
-
 static void LOADERDECL TexCoord_Read_Dummy()
 {
 	tcIndex++;