masaccio was born on 21 december, 1401, in the town of san giovanni valdarno, in the valley of the arno river, near florence. he was the son of a "notary", a person who writes legal documents. his older brother became a painter and moved to florence to the workshop of a painter called bicci di lorenzo. it is not known for certain, but it is thought that masaccio may have trained at the same workshop. masaccio's brother was nicknamed "lo scheggia" which means "the splinter", so it is thought that he was a skinny as masaccio was fat.