The Jesuits, especially around the 1600s emphasized adopting some customs of the local culture in order to spread Christianity, so you see Jesuits arriving in China and Japan learning the local language, dressing in local clothing, and even emulating some of the local traditions. Then they would use their advanced knowledge and willingness to provide education as a means of spreading Catholicism.
For example, Matteo Ricci, a Jesuit missionary to China impressed the Chinese so thoroughly that he was the first European ever invited to the Forbidden City. In the early 1600s, He was hugely influential in spreading more modern astronomical findings to China and he also provided the Chinese with the first modern (as in complete) map of the world. He was even nice enough to label it in Mandarin.
The Jesuits were extremely thorough at documenting their efforts so they were able to discern what worked from what didn't. Language became a very obvious barrier, namely that it was quite hard to translate some Catholic theological concepts (e.g. a Trinitarian God) into some languages. This meant that they emphasized learning the local language even more, but also would devote some effort to teaching locals Latin or some other suitable Romantic language - usually the one attached to the European power in control of the area. The effectiveness of temporary missions also proved to be problematic: converted locals "unconverted" after the missions left, so missions became more permanent and there was a focus on becoming a part of the local community. In practice, this meant constructing permanent locals for the missions (which usually had schools or universities attached).
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[1] This is probably best summarized by the concept of "Opus Dei" (God's Work) and the universal call to holiness. The idea is that your daily work, regardless of profession, should be considered an offering to God. If your work is an offering to God, then it must be your best work so you should not be either mediocre or half-assed about it.