Wassell was born in Kidderminster, England in 1814. In 1832 he left England for America, tracing the path of an uncle who preceded him from Philadelphia to Pittsburgh, to Cincinnati where he discovered that his relative had gone back to England. In Cincinnati Wassell learned carpentry, then took a group of workmen to Grand Gulf, Mississippi, and then to Little Rock, Arkansas, to do construction work on what is now called the Old State House. He farmed for seven years in Lonoke County before returning to Little Rock as co-owner of the Old Line Whig newspaper. He expanded his business interests to include a general and steamboat supply store, and a sawmill near Lewisburg on the Arkansas River. He also co-founded the Memphis and Little Rock Railroad, served as president of the Home Water Company and representative of Dun Mercantile Agency, and served as vice-president of First National Bank. Following successful self-defense in a legal proceeding, Wassell became educated as a lawyer.
Wassell married Margaret Spotts of Louisville, Kentucky, in 1837. They had eight children together.
- Goodspeed's History of Pulaski County, Arkansas (1889).