High Quality Content by WIKIPEDIA articles! Maarten Maartens, pen name of Jozua Marius Willem van der Poorten Schwartz (Amsterdam, 15 August 1858 - Doorn, 3 August 1915), was a Dutch writer, who wrote in English. He was quite well known at the end of the Nineteenth and the beginning of the Twentieth Century, in both the UK and the US, but he was soon forgotten after his death.