Since all the foot soldiers of the Tokugawa clan's immediate retainers became doshin when the Edo bakufu was established, various sorts of doshin were made; for example, Iga doshin and Koka doshin descended from ninja, a one-hundred matchlock infantry unit, Hachioji thousand doshin of country samurai, and so on.
江戸幕府成立時、徳川氏直参の足軽を全て同心としたため、忍者を祖先とする伊賀同心、甲賀同心、鉄砲組の百人組、郷士の八王子千人同心等、様々な同心職ができた。