The Texas question now came up to disturb politics and again bring slavery directly before the people. Texas had gained her independence from Mexico, and had applied, in 1837, to be received into the Union, but the offer was declined by President Van Buren. The tragic death of Mr. Upshur, Secretary of State, on February 28, 1844, and the appointment of Mr. Calhoun to that office, made possible the completion of a long conspiracy to admit Texas, and to further extend the slave area by a war with Mexico. A Treaty of Annexation was immediately prepared (April 12, 1844) and presented to the Senate, but was subsequently rejected. It then became apparent that the South intended to make a political issue of the Texas question, and there was great alarm in the North, for the admission of Texas meant a slave area capable of being divided into five or six slave States. In addition, it meant war with Mexico over disputed boundaries, and the fact that Mexico had not fully recognized the independence of Texas, and the result of that war would unquestionably be the acquisition of more area contiguous to the South. Mr. Clay and Mr. Van Buren at this time were the only ones prominently mentioned as possibilities for the Whig and Democratic nominations for the presidency; both published letters in which they opposed the annexation of Texas. Mr. Van Buren's letter cost him the Democratic nomination, for when the Convention met at Baltimore on May 27, 1844, he was unable to obtain a sufficient vote under the two-thirds rule, and the South forced the nomination of James K. Polk of Tennessee. This division on the slavery question in a Democratic Convention is of great historical importance as a link in the chain of events which led to the final great political division between the North and South. The Democratic Platform was emphatic in its support of slavery and the condemnation of the Abolitionists; it advocated the annexation of Texas and the occupation of Oregon, and the Democrats went into the campaign with the rallying cry of "Fifty-Four Forty or Fight," in the North--a promise of more free soil--and in the South the "Annexation of Texas."