His support for the New Deal and relationship with President Roosevelt crossed party lines, brought federal funds to New York City, and cut off patronage to La Guardia's Tammany enemies.

Achille worked as a trucker, a ship provisioner, and managed a hotel and turned down a job from the American Consul of Budapest due to the low pay.

[21] Raymond Willey, a friend of Achille and consular agent of Fiume, had La Guardia hired as a clerk in the Budapest consulate with a yearly salary of $100.

[33] Republican political boss Samuel S. Koenig convinced La Guardia to run in the 1919 special election for President of the New York City Board of Aldermen created by Al Smith's resignation to become governor.

[36] La Guardia considered running in the 1922 gubernatorial election and published his ideas for the Republican state platform in the column in the New York Evening Journal given to him by William Randolph Hearst.

[56] La Guardia considered running for reelection to Congress as a Democrat in the 1932 election and the option received support from William Green, John L. Lewis, and Robert F. Wagner.

[69] He secured the nominations and expected an easy win against incumbent Mayor John P. O'Brien; however, Joseph V. McKee entered the race as the nominee of the new "Recovery Party" at the last minute.

La Guardia's modernization efforts were publicized in the 1936 book New York Advancing: A Scientific Approach to Municipal Government, edited by Rebecca B. Rankin.

[72] An unorthodox Republican, he also ran as the nominee of the American Labor Party, a union-dominated anti-Tammany left wing group that supported Roosevelt for president beginning in 1936.

[69] He publicly supported groups that engaged in boycotts of German goods and spoke alongside Rabbi Stephen S. Wise, leader of the American Jewish Congress.

[69] During his reelection campaign in 1937, speaking before the Women's Division of the American Jewish Congress, he called for the creation of a special pavilion at the upcoming New York World's Fair, "a chamber of horrors" for "that brown-shirted fanatic," referring to Hitler.

In 1934 he went on a search-and-destroy mission looking for mob boss Frank Costello's slot machines, rounding up thousands of the "one armed bandits," swinging a sledgehammer and dumping them off a barge into the water for the newspapers and media.

In 1935 La Guardia appeared at the Bronx Terminal Market to institute a citywide ban on the sale, display, and possession of artichokes, whose prices were inflated by mobsters.

[82] He also came to the assistance of comic book creators Joe Simon and Jack Kirby, when they were openly threatened by sympathizers of Nazi Germany with their new superhero character, Captain America, when he arranged police protection.

[86] To obtain large-scale federal money the mayor became a close ally of Roosevelt and New Deal agencies such as the CWA, PWA, and WPA, which poured $1.1 billion into the city from 1934 to 1939.

[69] In 1941 during the run-up to American involvement in World War II, President Roosevelt appointed La Guardia first director of the new Office of Civilian Defense (OCD).

[65] As a congressman, La Guardia was a tireless and vocal champion of progressive causes, including relaxed restriction on immigration, removal of U.S. troops from Nicaragua to speaking up for the rights and livelihoods of striking miners, impoverished farmers, oppressed minorities, and struggling families.

He supported progressive income taxes, greater government oversight of Wall Street, and national employment insurance for workers idled by the Great Depression.

[65] In domestic policies, La Guardia tended toward socialism and wanted to nationalize and regulate; however, he was never close to the Socialist Party and never bothered to read Karl Marx.

Based on the theory that the lower courts are creations not of the Constitution but of Congress, and that Congress, therefore, has wide power in defining and restricting their jurisdiction, the act forbids issuance of injunctions to sustain anti-union contracts of employment, to prevent ceasing or refusing to perform any work or remain in any relation of employment, or to restrain acts generally constituting component parts of strikes, boycotts, and picketing.

Truman then gave him a major job as head of the United Nations Relief and Rehabilitation Administration (UNRRA), with responsibility for helping millions of desperate refugees in Europe.

Despite his declining health, La Guardia attacked the emerging "Truman Doctrine" that promised American financial and military intervention to stop the spread of Communism.

[130] They were living in Hungary and were arrested by the Gestapo on June 7, 1944,[131] Adolf Eichmann and Heinrich Himmler knew that Gemma was La Guardia's sister and ordered her to be held as a political prisoner.

[134] Gemma Gluck, who was held in Block II of the camp and assigned prisoner #44139,[131] was one of the few survivors of Ravensbrück,[135] one of the few American-born women interned by the Nazis along with Virginia d'Albert-Lake, and wrote about her time there.

After the liberation of the camps, Gemma later wrote that the Soviets were "violating girls and women of all ages", and the three struggled as displaced persons in postwar Berlin because they did not speak German and had no identity papers, money, or means of documenting where they had been.

[138][139][140] Gemma finally managed to get word to the Americans, who contacted Fiorello, who was then director of the United Nations Relief and Rehabilitation Administration (UNRRA) and had been unable to locate his sister and brother-in-law since their disappearance.

He worked to get them on the immigration lists but asserted in a letter, included in the appendix of Gemma's memoir, that her "case was the same as that of hundreds of thousands of displaced people" and "no exceptions can be made".

[141] La Guardia died of pancreatic cancer in his home at 5020 Goodridge Avenue, in the Fieldston neighborhood of Riverdale, Bronx, on September 20, 1947, aged 64.

[143] A 1993 survey of historians, political scientists, and urban experts conducted by Melvin G. Holli of the University of Illinois at Chicago ranked La Guardia as the best American big-city mayor to serve between the years 1820 and 1993.

[144] According to a biographer, Mason B. Williams, his close collaboration with Roosevelt's New Deal proved a striking success in linking national money and local needs.