His father was Raphael Isaac Keil, a German immigrant from Grätz, Prussia who worked as a tailor and changed his surname to Cowen when he briefly lived in England.

[2] He served as the paper's publisher for 27 year and was an active participant in the major issues and campaigns during the era of mass Jewish immigration.

He also proved instrumental in publishing works from, among other figures, Oscar S. Straus, Max J. Kohler, Henry Pereira Mendes, Emma Lazarus, Mary Antin, and Alexander Kohut.

[4] Cowen supported the organization of the Young Men's Hebrew Association and helped care for Russian Jewish immigrants that arrived in the early 1880s.

He arrived in Russia shortly after 937 Jews were killed all over the country during a wave of pogroms, and despite the danger he insisted on personally visiting some of the towns where Jewish homes were looted and razed to gather first-hand information he included in his official report.

He looked into conditions on Jews in other Southern and Eastern European countries, notably Romania, and was partly responsible for a large number of refugees immigrating to America.