Yes President Taft did
Ulysses Grant was given a horse named Cincinnatus by the people of Cincinnati.
Traveller.
General Thomas Jonathan "Stonewall" Jackson's horse was named Little Sorrel.
A horse named Traveler.
Whitey the horse was his pet in the White House according to www.factmonster.com.
General P.G.T. Beauregard's horse was named "General," often referred to as "General Beauregard's horse." This horse accompanied him during the Civil War, including at notable battles such as the First Battle of Bull Run. The horse became a symbol of Beauregard's leadership and presence on the battlefield.
Four current communities named Cincinnati and a fifth former community named Cincinnati Cincinnati, Arkansas Cincinnati, Indiana Cincinnati, Iowa Cincinnati, Ohio Cincinnati, California no longer exists.
Alexander the Great. He built many cities, several of them named after himself, and one named after his horse Bucephalus.
Charles Manson was born to an unmarried 16-year-old named Kathleen Maddox in Cincinnati General Hospital in Cincinnati, Ohio.
That most noble of all steeds was named Traveller. There is a very fun book by that title. It puports to be a first person account of the war as told by the horse.
Yes, George Washington named the horse Nelson after Thomas Nelson sent the horse to him as a gift when he heard that Washington was having a difficult time finding a new horse. This horse's whole story can be found at this link. http://www.mountvernon.org/educational-resources/encyclopedia/nelson
General Longstreet had two horses, one he used throughout the Battle of Gettysburg was named, "Hero", and the other, which was given to him after his duty in the West, by General Lee was named, "Fly-By-Night."