At fourteen he was legally old enough to be employed as a singing waiter, and he left home to prove he could fend for himself. It seems likely that he was also eager to put the language and customs of the old country behind him and begin living as a real American, speaking English and trading quips in the new slang with other struggling young immigrants excited to have the opportunity to invent new identities for themselves. Waiting on tables until six or seven in the morning, he soaked up the sounds that later emerged in his own hugely varied body of work: barroom ballads, ethnic songs, folksongs, novelty songs, ragtime, the blues, and jazz. He slept under tenement steps, ate scraps, and wore secondhand clothes. He later described those years as hard but good. “Every man should have a Lower East Side in his life,” he said.

He broke into Tin Pan Alley as a song plugger, but performing wasn’t enough for him. As he later told an interviewer, “Once you start singing, you start thinking of writing your own songs.” Still working as a waiter, he and the house piano player at Mike Salter’s café accepted their boss’s challenge to come up with a hit song to generate business for the restaurant. They wrote “Marie From Sunny Italy” and earned seventy-five cents in royalties. At first Berlin confined himself to writing lyrics, since he couldn’t read or write music or play any instrument. He became his own composer when he showed up at a publishing house with a novelty lyric and was offered a quick sale for the complete song. He made up a tune on the spot and sang it to a pianist in the office who wrote it out. For the rest of his life Berlin dictated his tunes to a musical secretary. His annotators and arrangers over the years included songwriters who later had considerable success of their own: Harry Akst, Arthur Johnston, Harry Ruby, Dave Dreyer. When George Gershwin auditioned for the job, Berlin turned him away, telling him, “You’ve got more talent than an arranger needs.”

An energetic and enterprising young man, Berlin ventured farther uptown, persuading name artists to sing his songs and placing some of his work in the Ziegfeld Follies of 1911. That same year, at the age of only twenty-three, he had his first international hit with “Alexander’s Ragtime Band.” A few years later he was the richest and most famous songwriter in the world.

He soon revealed himself to be as gifted in business as he was in music. In 1914 he became a charter member of the American Society of Composers, Authors, and Publishers (ASCAP), founded to protect songwriters’ rights and collect royalties for their work. Cautious with his considerable fortune, he moved to protect his work and make good investments for the future. His first step was to buy up the rights to all the songs he had ever written and go into business as Irving Berlin, Inc. He then turned to real estate. In 1921 the man who had spent his childhood in an airless tenement apartment with an outside toilet bought himself the top two floors of a West Forty-sixth Street brownstone with grilled windows, skylights, and a sumptuous bathroom. That same year, he and his partner, Sam Harris, built their own theater to house—and make more money from—their shows. The Music Box Theater still stands today at 239 West Forty-fifth Street.

Bright and witty, a self-made man of enormous and widely acknowledged accomplishment, Berlin must have loved being a leading cultural player in midtown Manhattan. He began turning up at the Algonquin Round Table in 1922 and soon found himself conducting the show No Sirree , with Robert Sherwood singing a Dorothy Parker song, Tallulah Bankhead dancing in the chorus line, and Robert Benchley delivering a comic monologue. At the painter Neysa McMein’s parties he often spent the evening sitting at the piano in the corner, composing a new tune. He was an insomniac who preferred to work at night anyway.

In his singing-waiter days he had taught himself to plink out a melody in F sharp, which uses all five black keys. In 1910 his mentor George M. Cohan gave him a transposing piano. A lever under the keyboard enabled a pianist to change keys without changing fingering. Berlin used a transposing piano all his life to hear his melodies in different keys; the instrument, which he referred to as “Buick,” accompanied him on all his travels. His writing method was to come up first with an idea and a title, then the main musical theme, and finally to work out the words and music simultaneously. “Writing both words and music,” he explained, “I can compose them together and make them fit. I sacrifice one for the other. If I have a melody I want to use, I plug away at the lyrics until I make them fit the best parts of my music and vice versa.”

Asked about Berlin’s place in American song, Jerome Kern said he had none: “He is American song.”

It was during his Algonquin days that the Round Table member Alexander Woollcott wrote the one book about Berlin that he allowed to appear in his lifetime. The more I read about his personal life, the easier it is to understand why he didn’t want it revealed. A Daughter’s Memoir chronicles the emotional and professional blows he absorbed and somehow survived. He seldom spoke of any of them, even with his own family.