A little dated, but plenty of history at: Omega Seamaster Information, eg:
How far back does the Seamaster line go?
Omega SeamasterOMEGA's line of water resistant watches dates all the way back to 1932. The Seamaster name was introduced in 1947. Up through the 1960's, the Seamaster models paralleled the traditional style of dress watches, such as the OMEGA DeVille (some were even labeled as a 'Seamaster DeVille'). While these watches were water resistant (back then, they could still use the term 'water-proof'), few had functions other than basic display of the time and occasionally the date.
In the 1970's, OMEGA took the Seamaster line in a much sportier and often trendier direction. During this decade, Seamasters took on a heavy sport and functional look and came with more diver-oriented features, such as higher depth ratings, calibrated rotating bezels, chronograph functions, and high-visibility dials.
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