Several schools predate the formation of the "United States" and Harvard is only one of them. It was created by legislative act in 1636 and named for its first major benefactor, John Harvard. While it was the first other schools followed and for the same purpose - the education of clergymen. Princeton (New Jersey College) was founded in 1746 by a Harvard grad and several other folks, all Yale grads (founded 1701), and all Presbyterians. A young James Madison attended the New Jersey school to learn seminary, later changing his mind and pursuing law instead. Many of his counterparts also went to William and Mary, another school that dates back to well before the 1770s. In 1693 William and Mary issued a charter for a;

perpetual College of Divinity, Philosophy, Languages, and other good Arts and Sciences.

It technically even predates the town of Williamsburg where it is located. It wasn't until Jefferson made some recommendations that divinity took a back seat at that institution. He would go on to found the University of Virginia in the 1810s - it was the first secular university in America (including colonial America).

I'm happy to expand on who started Harvard, what the original charter said, or why divinity schools exist if that's what you're really asking, but there was nothing new about that concept in 1636. It was just the first one in the North American colonies, it was started to educate the clergy, and was chartered by the colony itself.