Waltham is commonly referred to as Watch City because of its association with the watch industry. Waltham Watch Company opened its factory in Waltham in 1854 and was the first company to make watches on an assembly line. It won the gold medal in 1876 at the Philadelphia Centennial Exposition. The company produced over 35 million watches, clocks and instruments before it closed in 1957.
The name of the city is pronounced with the primary stress on the first syllable and a full vowel in the second syllable, WAWL-tham, though the name of the Waltham watch was pronounced with a reduced schwa in the second syllable: /ˈwɔːlθəm/. As most would pronounce in the British way, “Walthum”, when people came to work in the mills from Nova Scotia, the pronunciation evolved. The “local” version became a phonetic sounding to accommodate French speakers who could not pronounce in the British way.
Waltham was first settled in 1634 as part of Watertown and was officially incorporated as a separate town in 1738. Waltham had no recognizable town center until the 1830s, when the nearby Boston Manufacturing Company gave the town the land that now serves as its central square.