European contact with Japan
The Portuguese had reached Japan by 1543 and soon began trading. European trade brought firearms to Japan and the local smiths rapidly began to produce their own version and quickly adopted it into their warfare.
As well as trade, European interest in Japan centred around Christian missions. However by 1587 the Tokugawa government, irritated by factional disputes between missionary orders and worried about foreign influence, banned missionaries. By 1597 the active persecution of Christians had started.