What sports were played in the 1940's?

Assuming that you are talking about the United States, by
far the biggest sport in that decade was baseball.  Baseball was still the "national
pastime" of the country and was played and watched by more people than any other
sport.

Comparing the '40s with today, basketball was much
less popular both on the college and professional levels.  Football was popular as a
high school and college sport but the NFL was not the dominant league that it is
now.

A sport that was popular in those days (both for
spectators and for participants) but has declined in modern times was boxing.  Boxing
was still a major sport in those days whereas it is a fringe sport with very few
American stars today.

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