Hans Ansgar Reinhold (1897–1968) was a Roman Catholic priest born in Hamburg, Germany.[1][2][3][4] Reinhold took part in the Roman Catholic resistance to the Nazi regime until taking refuge in the United States.[1][2][3][4] He was a prominent liturgical reformer whose work was influential in shaping the changes to the Mass made at the Second Vatican Council.[1][2][3][4][5] Reinhold was also a prominent advocate for the introduction of modernist architectural ideas to the construction of Catholic churches in the United States.[6][7]