I suspect Manderly has at least 4000 heavy horse left in his hands

[Bright Blue Eyes]

Cavalry = heavy horse and light horse combined. Light horse would be several times the number of heavy horse.

Furthermore, the initial hosts of the Lannisters and the Starks both would have more (heavy) horse while the reinforcements (Oxcross for example) would contain more infantry.

[Free Northman]

The 500 horse quote Roose gives to Catelyn at the Twins is a very useful one. I can't believe I missed this before, but it finally gives us the means to accurately calculate a minimum number for the Bolton men in Robb's initial host.

Roose says that his force consists of primarily Bolton men as well as some Karstarks. But since we know that all the Karstark horse was with Robb until he beheaded lord Rickard, it follows that the Karstark men with Roose consisted of infantry only. This means that all 500 horse were Bolton men.

Now, given that we know the Karstarks brought 300 horse out of a total of 2300 men to Robb's banner, a similar ratio of horse to foot would mean that Roose Bolton brought about 3800 men in total to Winterfell.

Very interesting.

If the 500 were all that remained of say an initial larger force, then Bolton's total starting force numbered more than 4000. And this excludes any forces that Ramsay commanded in the North.

Altogether it confirms that Bolton's total strength is likely well in excess of 5000 men.

[Ramsay Gimp]

^Were the Boltons the largest force in Robb's army, then?

Also (and I apologize since this is kind of off-topic), does anyone have a figure for the number of men drawn directly from the Stark lands? As in, the lands surrounding Winterfell and directly under it's rule? Aren't the Tallharts minor lords of these lands?