Development of the Type 4 Chi-To began in 1943 as an intended successor to the Type 97-"Kai" Shinhoto Chi-Ha. The Army Technical Bureau had been working on the Type 4 Chi-To as the counter to the M4 Sherman, but there were problems and delays in the program. As a result a stopgap tank was required. The Type 3 Chi-Nu medium tank was developed to cope with the M4 Sherman. Finally, the first prototype Type 4 Chi-To was delivered in 1944. Similar in appearance but significantly larger than the Type 97, it was the most advanced Japanese tank to reach the production stage.