Tây Sơn District occupies the western reaches of Bình Định Province, where the lowland plain begins its transition to the Central Highlands. The Kôn River runs through the district in a southeast direction, flowing from Vĩnh Thạnh District down through the district capital of Phú Phong Town and on toward An Nhơn. National Highways 19 and 19B both pass through the valley, and An Khê Pass, on Highway 19, marks the boundary between Tây Sơn and the highlands province of Gia Lai — a natural gateway that has channeled trade, armies, and travelers for centuries. The climate is tropical monsoon: a dry season from March through October that brings intense heat (the record high is 39°C), followed by a cool, wet season from November to February. The population of the district stood at 176,600 people before its administrative dissolution.

The Tây Sơn brothers — Nguyễn Nhạc, Nguyễn Lữ, and Nguyễn Huệ — grew up in the village of Tây Sơn and settled in nearby Kiên Mỹ, now part of Phú Phong town. Their uprising, which began in 1771, eventually toppled both the Nguyễn lords ruling the south and the Trịnh lords controlling the north, a feat no single force had managed in generations of Vietnamese civil war. The youngest brother, Nguyễn Huệ, crowned himself Emperor Quang Trung and in 1789 routed a massive Qing dynasty invasion force at the Battle of Ngọc Hồi-Đống Đa in a campaign of startling speed. Bình Định Province still claims this history with pride — the dynasty lasted only a generation, but the brothers themselves became foundational figures in Vietnamese national identity. Their childhood valley remains the emotional center of that story.

Beyond the Quang Trung Museum and its carefully preserved artifacts, the district holds older evidence of the cultures that came before the Tây Sơn era. The ruins of Dương Long Cham Temple in Tây Sơn are remnants of the Cham civilization that preceded Vietnamese settlement in this region, a culture that built its towers across what is now central Vietnam for over a millennium. The district also contains Hầm Hô, a rocky stream area known for its natural pools and carved-granite scenery — the Kôn River's tributary behavior creating small gorges and swimming holes that draw visitors away from the historical sites into the terrain itself. The landscape holds multiple layers of time.

As of July 1, 2025, Tây Sơn District was officially dissolved and reorganized into communes under Gia Lai Province, part of a broader Vietnamese administrative consolidation. The physical geography remains, and Phú Phong Town remains the hub of the former district. But the administrative unit of Tây Sơn District — 176,600 people, roughly 40 kilometers inland from Qui Nhơn, 20 kilometers from Phù Cát Airport — has been folded into the larger provincial structure. What endures is what always mattered here: the river valley, the pass into the highlands, and the memory of three brothers who traded and farmed this ground before they changed the country.