Japan Proletarian Party

{{Short description|Japanese leftist political party}}

{{Expand Japanese|topic=hist|日本無産党|date=December 2020}}

{{Infobox political party

| name = Japan Proletarian Party
日本無産党

| native_name = Nihon Musantō

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| colorcode = red

| abbreviation =

| founder = Suzuki Mosaburō
Katō Kanjū

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| founded = March 1937

| dissolved =

| banned = 23 December 1937

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| student_wing =

| youth_wing =

| wing1_title = Labour wing

| wing1 =

| wing2_title = Women's wing

| wing2 =

| wing3_title = Peasants' wing

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| ideology = Anti-Shakai Taishūtō
Revolutionary socialism
Socialism
Agrarian socialism

| position = Left-wing to Far-left

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| country = Japan

}}

{{Nihongo|Japan Proletarian Party|日本無産党|Nihon Musantō}} was a short-lived leftist political party in early Shōwa period Japan.

The Nihon Musantō was founded by Suzuki Mosaburō and {{illm|Katō Kanjū|ja|加藤勘十}} (1892–1978) in March 1937, as a political wing of the labor union movement.{{cite book |title=Japan encyclopedia |first=Louis |last=Frédéric |translator-first=Käthe |translator-last=Roth |publisher=Harvard University Press |date=2005 |isbn=978-0-674-01753-5 |page=[https://books.google.com/books?id=p2QnPijAEmEC&dq=Japan+Proletarian+Party+showa&pg=PA709 709]}} Katō, its chairman, won a seat in the 1937 general election, but the party failed to create much popular support against the rising forces of militarism and against the rising inflation in the Japanese economy.

In December 1937, its members were arrested in the Popular Front Incident, and the party was disbanded.