Mainero is a municipality located in the Mexican state of Tamaulipas. Its capital is called Villa Mainero and had 338 inhabitants during a 2020 …Mainero is a municipality located in the Mexican state of Tamaulipas. Its capital is called Villa Mainero and had 338 inhabitants during a 2020 INEGI census. The municipality as a whole had 2 048 inhabitants. Other localities include José Guadalupe Mainero, Guadalupe Mainero and Guadalupe Mainero. All named after Guadalupe Mainero, a Mexican journalist, teacher and governor of Tamaulipas between May 4, 1896 and July 31, 1901.