Blue Duck was captured and going to be hung, but grabbed a deputy and jumped out of a 4 story window killing both on impact
July Johnson's wife?, Steve Buscemi/Luke and the big Buffalo Hunter were killed by Indians
when Woodrow goes back to Lonesome Dove a reporter tells him that Xavier Wanz, the bartender burned himself up in the saloon because he was heartbroken (over Lorena leaving)
btw Gus died because he wouldn't let the doctor take off his other leg, when he woke up the Dr had only removed one. He said he would have "shot him dead" if he had taken them both.
you should read the book too, it's excellent
Pea was led back to safety by Deets ghost?
SPOILER:
Although author Larry McMurtry claims that they have no basis in historical fact, it seems likely that the characters of Augustus McCrae and Woodrow Call are modeled after cattlemen Oliver Loving and Charles Goodnight, respectively. Upon the death of their scout, an escaped slave named Bose Ikard, Goodnight carved a sign for his grave, just as Call does for Joshua Deets. Loving died of blood poisoning from Indian arrows, just like McCrae. Upon his death, Goodnight carried his body back to Texas for burial, just as Call does for Augustus. Indeed, Goodnight is actually featured as a character in a small scene in the original novel.