Your challenge, should you choose to accept it, is for a country which has had a republican form of government to become a monarchy no earlier than January 1, 1900.
The only OTL example I can think of is Spain, but that only sort-of counts (from the Second Spanish Republic to Franco's Spanish State to the modern Kingdom).
The only OTL example I can think of is Spain, but that only sort-of counts (from the Second Spanish Republic to Franco's Spanish State to the modern Kingdom).