In July/August 1914, he was playing in Mannheim at (the 19th DSB Congress, when it was interrupted by the start of World War I. After the declaration of war against Russia, eleven Russian players (Alekhine, Bogoljubow, Bogatyrchuk, Flamberg, Koppelman, Maljutin, Rabinovich, Romanovsky, Saburov, Selezniev, Weinstein) from the Mannheim tournament were interned in Germany. In September, four of them (Alekhine, Bogatyrchuk, Saburov, and Koppelman) were freed and allowed to return home through Switzerland. As an internee, Weinstein played seven tournaments. He took 7th at Baden-Baden 1914 (Alexander Flamberg won), took 6th at Triberg 1914/15 (Efim Bogoljubow won), tied for 5-6th, and twice took 6th at Triberg 1915 (all tournaments Bogoljubov won), tied for 4-5th at Triberg 1916 (Ilya Rabinovich won), and took 4th at Triberg 1917 (Rabinovich and Alexey Selezniev won).http://www.anders.thulin.name/SUBJECTS/CHESS/CTCIndex.pdf Name Index to Jeremy Gaige's Chess Tournament Crosstables, An Electronic Edition, Anders Thulin, Malmö, 2004-09-01
