Here is a collection of posters from various expositions held in Japan in the 1920s to 1940s.
National Industrial Exhibition - Himeji, 1926 [+]
National Products Progress Exhibition - Sapporo, 1926 [+]
Grand Exposition in Commemoration of the Imperial Coronation - Kyoto, 1928 [+]
Sea and Air Exhibition - Tokyo, 1930 [+]
Sea and Air Exhibition - Tokyo, 1930 [+]
The National Products Progress Exhibition - Kagoshima, 1931 [+]
National Horse Exhibition - Osaka, 1933 [+]
Tourism Industry Exhibition - Nara, 1933 [+]
Yokohama Exposition - Yokohama, 1935 [+]
National Exposition - Iga-Ueno, 1935 [+]
National Defense and Resources Exposition - Himeji, 1936 [+]
National Defense and Resources Exposition - Himeji, 1936
National Defense and Resources Exposition - Himeji, 1936
Exposition Commemorating Hakata Port Construction - Fukuoka, 1936 [+]
Exposition Commemorating the Construction of Hakata Port - Fukuoka, 1936 [+]
Japan-Manchuria Industrial Exhibition - Toyama, 1936 [+]
Nagoya Pan-Pacific Peace Exposition - Nagoya, 1937 [+]
Nagoya Pan-Pacific Peace Exposition - Nagoya, 1937 [+]
Nangoku Tosa Exhibition - Kochi, 1937 [+]
International Hot Spring Tourism Exposition - Beppu, 1937 [+]
Second Sino-Japanese War Exhibition - Osaka, 1938 [+]
Greater East Asia Construction Exposition - Osaka, 1939 [+]
National Defense Science Exposition - Tokyo/Kanagawa, 1940 [+]
National Defense Science Exposition - Hyogo, 1941 [+]
National Defense Science Exposition - Hyogo, 1941
National Defense Science Exposition - Hyogo, 1941
Asia Development and Defense Exposition - Toyota City, 1941 [+]
[Via: Nihon no Hakurankai, published by Heibonsha Limited, 2005]