Mathias Nilsen (November 22, 3834 - April 29, 3909) was a Kazulian politician who served as Statsminister of Kazulia from 3885 to 3889 and again from 3891 to 3896. He founded the governing Labour Party in 3882 and was the party's inaugural leader, serving until his retirement in 3896. Before establishing the Labour Party, Nilsen was a leading trade unionist.