Why is the Uzumaki clan symbol more like a trademark in Konoha
The Uzumaki, being descendants of Asura Ōtsutsuki, also shared distant blood relation with the Senju clan. Through the years, the Uzumaki and Senju kept close ties, with members at times marrying between clans, as with Hashirama Senju and Mito Uzumaki. Following the founding of Konohagakure at the end of the Warring States Period, the Senju chose to symbolise their clans' friendship by adding the Uzumaki's emblem to Konoha's flak jackets. Konoha and the Uzumaki's own Uzushiogakure remained close allies over the following decades, with the Uzumaki providing fūinjutsu (among other things) to Konoha whenever there was a need.  


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