This paper analyses the occupational patterns in Mumbai's textile mills from 1870 to 2006. It utilises British colonial census data from 1872 to 1941, the 1940 Bombay Mill Owners Association Survey, and original survey data collected in 2009 from 924 former mill workers. The study reveals how caste norms influenced occupational mobility and access to employment. Workers from higher castes, such as Brahmins & Rajputs, dominant Maratha castes, and Other Backward Classes (OBCs) demonstrated occupational flexibility, transitioning between the least desirable roles in the Ring and Spinning departments and the most desirable, prestigious, higher-paid positions in the Weaving department. Dalits (untouchables) were explicitly prohibited from entering the weaving departments and faced severe restrictions. Even Dr B.R. Ambedkar's efforts during the 1928 strike to secure Dalit access to these departments faced strong resistance from Maratha workers and indifference from mill owners. The exclusion of Dalits from weaving jobs was enforced through the invocation of caste-based notions of "purity" and "pollution." Despite the persistence of structural discrimination throughout the twentieth century, urban industrial settings provided Dalits with opportunities for monetary compensation and political mobilisation that were not available in rural areas. The study demonstrates the marginalisation of Muslim weavers, particularly Julaha-Ansaris, who, despite their traditional weaving skills and initial dominance, were progressively excluded from the 1960s onwards through communal tensions, technological changes, and discriminatory hiring practices.