Constitution Day is observed in Mexico on the first Monday in February, celebrating the ratification of the 1917 Constitution, which was adopted following the Mexican Revolution. This constitution was notable for being the first in the world to establish social rights and served as a model for subsequent constitutions, including those of Russia in 1918 and Germany in 1919. Originally celebrated on February 5, the holiday's date was changed in 2005 due to amendments that also included the banning of capital punishment and modifications to labor laws. Constitution Day is a public holiday in Mexico, marked by large parades across the country, allowing citizens to commemorate this significant historical event.