Located in Thailand’s lower northern region, Phetchabun has a rich history that spans prehistoric settlements, cultural integration, and political significance. Its name likely originated from "Phetchabura," meaning "land of crops," indicating its long-standing agricultural abundance. Evidence of prehistoric communities in Phetchabun includes stone tools and burial sites dating back 3,000–4,000 years, found in Wang Pong, Chon Daen, and Si Thep districts. Si Thep, in particular, is recognized as an early historic site over 2,000 years old, containing remnants of the Dvaravati and Khmer civilizations, including artifacts from Hindu and Buddhist religions.

During the Sukhothai era, Phetchabun served as a southeastern vassal state. It later became strategically important under the Ayutthaya Kingdom, where it was governed by local rulers, including Phraya Phet Rattanasongkhram. The city’s role as a key Ayutthaya stronghold is evident in its repeated mention during regional conflicts. During World War II, Prime Minister Phibunsongkhram selected Phetchabun as a potential new capital, but the plan was ultimately abandoned.

Phetchabun's geography, featuring the Pasak River and abundant resources, supports extensive agriculture, including tobacco, rice, and sugarcane production. The area also holds Cold War-era monuments from Thailand’s communist insurgency period on Khao Kho, now popular for tourism. Phetchabun has thus evolved from an ancient agricultural hub and strategic center to a thriving modern province rich in historical and cultural sites.