While the 1947 Partition carved Punjab and Bengal in half, Sindh was handed to Pakistan entirely intact. Despite dominating the province's major cities, Sindhi Hindus faced an impossible map.
The core reason was demographics. The British formula only divided provinces that contained geographically contiguous districts where Muslims and non-Muslims each formed a majority. Sindh had an overall Muslim majority of roughly 73%, with Hindus making up about 26% of the population. Unlike in Punjab and Bengal, where minority populations were concentrated in massive, separable blocs in the east or west, the Sindhi Hindu population was not geographically concentrated enough to form a single district-level majority.
Sindhi Hindus were overwhelmingly an educated, urban mercantile class. They dominated the commerce, education, and civil administration of cities like Karachi, Hyderabad, Sukkur, and Shikarpur, but they were surrounded by vast rural hinterlands that were almost entirely Muslim. Because there was no contiguous block of Hindu-majority districts, the British Boundary Commission was never even tasked with drawing a line through Sindh.
Geography also made creating a Hindu enclave impossible. Even if the British had wanted to carve out a territory for the Hindus of Karachi, there was no way to connect it to India. Sindh was bordered by the Arabian Sea to the south, Balochistan to the west, and Muslim-majority West Punjab to the north. Its only border with India was the desolate Thar Desert to the east, far from the urban centers where Sindhi Hindus actually lived.
Without a demographic or geographic basis for partition, the decision fell to the Sindh Legislative Assembly. On June 26, 1947, the assembly held a special session to decide its fate. Reflecting the province's overall demographics, the assembly voted 33 to 20 to join the new Constituent Assembly of Pakistan.
Because their homeland could not be partitioned, Sindhi Hindus found themselves entirely inside the borders of a newly formed republic. In the months following Partition, escalating communal violence—culminating in the Karachi riots of January 1948—forced nearly the entire Sindhi Hindu community to abandon their ancestral homeland. They evacuated by sea and train to India, leaving behind vast properties, businesses, and a province that was completely absorbed into Pakistan.