I don't know what you mean by "outside influences?" There was flourishing "Dutch Studies" in the Tokugawa period where Japanese scholars poured over translations of Dutch books about medicine, art, science, politics, history, etc. There was a ton of trade between Japan and China and Korea and semi-regular visits by Korean diplomats to Edo. Japan also engaged in some trade with the Ainu up north and with the Ryukyuans down south.