After annexation Pease represented Brazoria County in the first three legislatures and authored the Probate Code of 1846. In 1851 he made an unsuccessful run for the governorship. Two years later he won the office and was reelected in 1855. Pease was an outstanding governor. Among his important achievements was his pioneering effort to persuade the legislature to establish a system of public education and a state university. Though this effort proved largely premature, Pease's administration did establish the permanent school fund, and his vision laid the groundwork for future achievement. He also worked to encourage railroad construction in Texas, to put the state penitentiary on a self-supporting basis, and to establish reservations to civilize and educate the state's Indian population. In addition, he supervised the building campaign that led to the completion of the Governor's Mansion, the General Land Office building, the State Orphan's Home (now the Corsicana State Homeqv), and a new Capitol. Perhaps his most significant accomplishment was the settlement of the public debt of the state, by which he made available funds for the establishment of a hospital for the mentally ill and schools for the deaf and blind, all of which he had recommended to the legislature. Upon his retirement from office in 1857, the state was in excellent financial condition.
In 1859 Pease aligned himself with the Unionist faction in Texas politics. He remained active in this movement into the early months of the Civil War, after which he quietly maintained his loyalty to the Union until the end of the conflict. In 1866 he lost a bid to become governor again in the first election of the Reconstruction era. Early in 1867 he helped organize the Republican party in Texas. Later that year Gen. Philip H. Sheridan removed Governor James W. Throckmorton from office and appointed Pease in his place. Pease's subsequent efforts to reorganize the state government and bring accountability to its actions were met by conflict within the Republican ranks and bitterness toward the chief executive by the former Confederate majority in the state. Pease resigned from the governorship in 1869 because of differences with Gen. Joseph J. Reynolds over Reconstruction policies that Pease considered radical and despotic. Throughout the remainder of his life Pease remained actively interested in political affairs in the state. He was president of the non-partisan Tax-payers' Convention of 1871, which opposed many of the measures of Governor Edmund J. Davis's administration. In 1872 he was chairman of the Texas delegation to the national Liberal Republican convention. In 1879 President Rutherford B. Hayes appointed Pease to the collectorship of customs at Galveston. In the closing years of his life Pease practiced law in Austin, engaged in various business ventures, and lived a quiet life with his wife, the former Lucadia Christiana Niles, of Poquonock, Connecticut, whom he had married in 1850, and their two daughters. A third daughter had died in childhood. Pease died on August 26, 1883, after an attack of apoplexy and was buried in Austin.
30° 16.608, -097° 43.631