The Republic of Texas was an independent nation that existed from 1836 to 1845. It was formed after the Texas Revolution, which resulted in Texas gaining independence from Mexico. The Republic of Texas was eventually annexed by the United States in 1845.
In the context of the keyword “sdn republic of texas 2025”, “sdn” is most likely an acronym or abbreviation. Without more information, it is difficult to say what “sdn” stands for in this context. However, we can speculate that it may refer to the “State of Texas” or the “Sovereign State of Texas”.