Dinosauricon
Lieutenant
These were mentioned in the original series, and expanded a bit in the novels and audio series. Basically, mid 20th millenium, Earth and various other planets are involved in massive wars with the Daleks and Cybermen. Not quite on the scale of the Time War, but problematic enough.
 
The human Wars with the Daleks might have ended when the Daleks decided they wanted to tackle Gallifrey ("One minute they were the biggest threat in the Universe, then they vanished" "They went to fight in a bigger war...the time war"). Interestingly, although I haven't read it, I think the latest Tennant Dalek novel is actually set during the wars, hence giving Tennant a Dalek story where he doesn't face the post-TW Daleks (That's Time War, not Torchwood).
 
 
The Cyberwars-where humans battle Cybermen-are also mentioned in the Next Doctor Confidential thingy with Captain Jack, and form much of the backstory of REVENGE OF THE CYBERMEN and EARTHSHOCK. They're against the Mondasian/Telosian Cybermen, of course. The weird thing though is that this presents a continuity error. REVENGE Is supposed to be in the 29th century, whereas EARTHSHOCK is set in the 25th. Yet not only are the Earthshock Cybermen more advanced, they have a clipshow and plot summary of Tom Baker from REVENGE, which hasn't happened yet! (Do'h!).
 
Anyway, I think the Cyberwars are detailed in some of the audios such as the Cybermen series. Not sure about that, though.
 
 
Of course it's entirely possible that the events of the new series have altered things, especially with the Daleks/Cybermen invading or trying to invade Earth much earlier than they did in the original series.
	
		
			
		
		
	
				
			The human Wars with the Daleks might have ended when the Daleks decided they wanted to tackle Gallifrey ("One minute they were the biggest threat in the Universe, then they vanished" "They went to fight in a bigger war...the time war"). Interestingly, although I haven't read it, I think the latest Tennant Dalek novel is actually set during the wars, hence giving Tennant a Dalek story where he doesn't face the post-TW Daleks (That's Time War, not Torchwood).
The Cyberwars-where humans battle Cybermen-are also mentioned in the Next Doctor Confidential thingy with Captain Jack, and form much of the backstory of REVENGE OF THE CYBERMEN and EARTHSHOCK. They're against the Mondasian/Telosian Cybermen, of course. The weird thing though is that this presents a continuity error. REVENGE Is supposed to be in the 29th century, whereas EARTHSHOCK is set in the 25th. Yet not only are the Earthshock Cybermen more advanced, they have a clipshow and plot summary of Tom Baker from REVENGE, which hasn't happened yet! (Do'h!).
Anyway, I think the Cyberwars are detailed in some of the audios such as the Cybermen series. Not sure about that, though.
Of course it's entirely possible that the events of the new series have altered things, especially with the Daleks/Cybermen invading or trying to invade Earth much earlier than they did in the original series.