Othniel Charles Marsh was born in 1831, and came from more modest roots than Cope. His father was a farmer, but the young Marsh had the advantage of having a rich uncle, George Peabody. Peabody paid for Marsh’s education, sending him to Yale, and later financing the Peabody Museum of Natural History at Yale (where Marsh became the curator). Marsh later became the first professor of Paleontology in North America. He was a bit of a loner, and never married (though that may be in part due to his uncle’s controlling nature). Marsh met Cope in Berlin in 1864, and while many have said the two were friends, I think friendly colleagues is probably more accurate.
Perhaps because they were so different, and working in such a small field, competition was inevitable. However, there were two things that really set off their rivalry. In 1868, Cope was doing field work in New Jersey, where the first Hadrosaurus had been found by his mentor Joseph Leidy. Cope happily showed Marsh around the fossil bed. Unbeknownst to Cope, however, Marsh had bribed the New Jersey quarry owners to send fossil finds to him first, sabotaging Cope’s work.
Then, the same year, Cope discovered a brand-new plesiosaur (an ancient marine reptile). Naming rights were given to whoever first published a find, so he was in a hurry. He named the creature Elasmosaurus. It was Marsh who pointed out, perhaps a bit too gleefully, that in his haste Cope had made a serious error. Cope had mounted the creature’s skull on the tip of its tail, rather than the end of the neck. To add insult to injury, when Cope tried to hunt down and destroy all of the copies of the journal that his find had been published in, Marsh refused to let go of his copy.