José María Rómulo Díaz de la Vega Fuentes (23 May 1800 — 3 October 1877) as commander of the garrison in Mexico City was the de facto president of Mexico in 1855 after the resignation of President Martin Carrera during the revolutionary Plan of Ayutla left a power vacuum.

He also fought in the Mexican-American War and he was captured at the Battle of Resaca de la Palma on May 9, 1846.

[1][2] Díaz de la Vega was military commander of Puebla in 1849 and Tamaulipas in 1850 and then Governor of Yucatán in 1853.

After his presidency, Díaz de la Vega was a member of the Assembly of Notables who invited Maximilian of Habsburg to be emperor in 1863.

After the triumph of the Republic, he was sentenced to two years imprisonment, but the penalty was switched by confinement in Puebla, where he died in October 1877, exactly twenty-two years to the day his tenure as president ended.