Why did Philadelphia have WASP mayors until the 1960s?

[King of Kensington]

Most of the big Eastern cities were known for their Irish politicians and political machines, yet Philadelphia was dominated by Republicans until the 1950s and didn't elect their first non-WASP (Irish Catholic) mayor until 1962 (James Tate).  Why did the WASP establishment hang to political power for so long?  Was Philadelphia more "WASP" or have a significantly larger "old stock" population than New York, Boston, Chicago, etc.?

[All Along The Watchtower]

IIRC, the Italian population in Philadelphia were a big part of the Republican machine in the city. Maybe that had something to do with it?

[patrick1]

Think there are a number of factors: powerful Tammany like corrupt machine (only Republican), mid Atlantic was hotbed of Know nothing and nativism, black population was late to turn Democrat, didnt have immigrant numbers like New York, organized labor late to the game.

[King of Kensington]

Philadelphia had a smaller immigrant population and was more Black.

In 1890 it was 56% foreign stock and 54% in 1920.  New York was 80% in 1890 and 76% in 1920.  Chicago was 78% in 1890 and 72% in 1920.  Boston interestingly had a higher percentage of foreign stock in 1920 (73%) than in 1890 (68%).  

In 1880, Philadelphia was 27% first- and second-generation Irish and 16% first- and second-generation German (don't have foreign stock figures for 1890).  New York that year was 35% Irish and 30% German and in 1890 it was 29% German and 28% Irish.  Chicago in 1890 was 32% German and 17% Irish.

Boston the only figure I could was an estimated 42% first- and second-generation Irish in 1885.  The rest of the "foreign stock" would have been mostly made up of Canadians from the Maritimes and England.

I don't have the figures but I believe Philadelphia had the highest proportion of English, Scots and Welsh of these cities.

ETA: In other words, the combined Irish and German population ca. 1890 would have constituted a majority in NYC (which they would have lost after 1900) and probably Chicago (i.e., if the 3rd generation is included), Boston was approaching majority-Irish and they would have outnumbered the Yankees (not too familiar with the Canadian Maritimers politically but there would have been a class difference between them and Yankee Protestants).  Philly was almost still-majority white Protestant at the time and the "old colonial stock" probably retained a plurality until after 1900.

Of course, the Germans politically were quite heterogeneous: Protestant and Catholic, there were radical socialist elements etc.

[King of Kensington]

Also, I guess there wasn't/isn't really an equivalent of Chestnut Hill in New York, Chicago etc.

[traininthedistance]

Also, I guess there wasn't/isn't really an equivalent of Chestnut Hill in New York

Riverdale?

[King of Kensington]

I suppose, but Riverdale is a heavily Jewish neighborhood - probably since the 1930s or 1940s.

Chestnut Hill was quite WASPy until well after the war.

[patrick1]

I suppose, but Riverdale is a heavily Jewish neighborhood - probably since the 1930s or 1940s.

Chestnut Hill was quite WASPy until well after the war.

Upper East Side of NYC was considered a WASP bastion.