Because they know that word, and not another more geographically relevant word for the time period? They could have just repeatedly said "the 1850s" but they w

Because they know that word, and not another more geographically relevant word for the time period? They could have just repeatedly said "the 1850s" but they wanted to be more diverse. Kind of like how "temblor" gets hauled out every time someone writes about earthquakes. I'm super-curious if you know of a term for the 1850s that is geographically relevant to New York, or the region?