There is some debate over whether to date Steinitz' reign as world champion from his win over Anderssen in 1866, or from his win over Zukertort in 1886. The 1886 match was clearly agreed to be for the world championship, but there is no indication that Steinitz was regarded as the defending champion. There is also no known evidence of Steinitz being called world champion after defeating Anderssen in 1866. It has been suggested that Steinitz could not make such a claim while Morphy was alive (Morphy died in 1884). There are a number of references to Steinitz as world champion in the 1870s, the earliest being after the first Zukertort match in 1872. Later, in 1879, it was argued that Zukertort was world champion, since Morphy and Steinitz were not active. But later in his career, at least from 1887, Steinitz dated his reign from this 1866 match; and early sources such as the New York Times in 1894, and Emanuel Lasker in 1908, do the same; as did Reuben Fine in 1952.