Who was the first American to go into suborbital flight and which rockets was used?

The first animal to make a suborbital space flight from American soil was Albert, a rhesus monkey. He flew on a V2 rocket and suffocated on his way. Another monkey named Albert II made a successful journey, but died from impact on its return.

The first Human American that made a sub orbital flight was Alan Shepard in May 5, 1961, who later Commanded Apollo 14. He flew in a Redstone rocket during his sub-orbital flight.