Len,

Yes, that is true. At least 40% of the male slaves of military age in Kentucky served in the Union army. The attempts to enlist only free black Kentuckians broke down and by the summer of 1864 the Union army accepted black volunteers, slave or free. The Union army at first attempted to give former slaveowners a bounty of a few hundred dollars, but that did not last. There are records at the National Archives that indicate some slaveowners did allow their slaves to enlist. However, Slaves were leaving in large numbers to join the Union army at Camp Nelson and Camp Dick Robinson regardless of their masters' allegiance.

It is probably necessary to mention that it was harder for Kentucky slaves to enlist. Even if a male slave could enlist, they were reluctant to leave their families for fear of reprisal from their former masters. Much of the guerrilla violence and political conflict in Kentucky during the last several years of the war was due to local resistance to black enlistment and the slow destruction of slavery in the state. Many more Black Kentuckians would have joined if they had the chance.

So Kentucky was the state with the most black enlistment, but also the state with the largest number of military aged white men (close to 70%) who fought for no one. The number of black men who did not enlist was a little lower, around 60%, but I admit they may not have had an opportunity to(or they enlisted in other states). Besides, black enlistment only occured during the last year and a half. White Kentuckians had the entire war to join up for either side, but many did not.

Kentucky had 51,743 white troops serving (around 20% of eligible males), and 23,703 black troops in the Union army.

Compare that to nearby Indiana, which contributed 193,748 white troops (roughly 60% of eligible males) and 1,537 black troops. And some of those black soldiers were former slaves who came from Kentucky or other slave states to enlist.

This says alot about Kentucky as part of a border region.
There was more at stake, and the issues of emancipation were being played out within the state, not elsewhere.

Stephen