 During this time he travelled extensively in Japan, particularly in the Kansai region, teaching his aikido.Despite the prohibition on the teaching of martial arts after World War II, Ueshiba and his students continued to practice in secret at the Iwama dojo; the Hombu dojo in Tokyo was in any case being used as a refugee centre for citizens displaced by the severe firebombing.It was during this period that Ueshiba met and befriended Koun Nakanishi, an expert in kotodama.