The Iron Triangle by James M. McPherson — though primarily about the wider Capital District, McPherson's account of the industrial transformation of the Hudson Valley in the 19th century gives Troy its proper context: not a backwater but the centre of a manufacturing revolution that supplied the infrastructure of a continent.
The Collar City by Howard Nickerson traces Troy's oddly specific dominance in the production of detachable shirt collars and cuffs, an industry that at its peak employed thousands of women in Troy's laundries and factories and made the city an early centre of labour organisation. The story of the collar is the story of 19th-century American consumerism in miniature.
Herman Melville's letters and journals reference his time visiting relatives in the Albany and Troy area, and the Hudson Valley landscape saturates Pierre, or The Ambiguities (1852), his least-read and most neurotic novel. Reading it in Troy, looking out at the same river, is an experience.
Martin Luther King Jr. visited Troy and the speeches he gave in the Capital District during the early 1960s are collected in various editions of his writings. The city had an active civil rights movement, and reading those speeches alongside a walk through downtown gives the history of the place an unexpected additional layer.