In terms of Indian history books, Sitamarhi might be a divided part of Muzaffarpur district of Bihar which came into existence on 11th December 1972. But the people, the land, the civilization has its roots well rooted in best Mythological book of all times….”Ramayana”.
According to Ramayana, King Janak who was father of Goddess Sita ruled a kingdom of Janakpur which now lies in Nepal. King Janak was blessed with a wish from God Indra (Rain God) that if he ploughs even a barren field, it will become productive. Once southern part of his kingdom came into grab of drought and farmers and their families were dying of hunger. Then the King came to rescue of its people. He ploughed a barren field in a village called “Punaura – A village of mordern Sitamarhi” of his kingdom. While ploughing the field his oxen hit a pot. The pot had a baby girl in it. The baby was Goddess Sita. The King who did not had any baby, gave his name to the baby. It is said and seen that Sitamarhi didnt had any drought since then due to the grace of God Indra.
If you have guts to believe this mythological story (in this Kalyug era), then just try to believe one more fact…. Lord Rama would have traveled through the “Soil of Sitamarhi” to break the bow (eg: bow & arrow) and marry Goddess Sita.