The classical symphony—a piece for orchestra, generally in four contrasting sections or movements—was so perfected by Mozart and Joseph Haydn in the late 18th century, that Beethoven, when he came along, had to shake things up to make his mark.

Beethoven’s symphonies broke the classical mold—or rather, extended it with sudden shifts of mood and tempo expressing powerful, personal emotions. His Ninth Symphony shocked audiences with its unprecedented length, well over an hour, its unheard-of use of singers and a choir, and its harmonies, so unusual that one critic attributed the “wrong notes” to the composer’s loss of hearing.

After Beethoven’s death, Brahms, Tchaikovsky, Bruckner and others took the symphony in new directions, but by the time of Gustav Mahler (1860-1911) the form seemed exhausted and played out. Whatever could be done with a symphony had already been done. 

But Mahler wanted to write symphonies. The challenge was especially hard because he was a part-time composer. His day job as one of his era’s most acclaimed and sought-after conductors kept him so busy that he only had time to compose during summer holidays.

From 1893 on, Mahler spent summers writing his symphonies in the peaceful Austrian countryside. Nature always inspired his creativity. During the rest of the year, he conducted in Europe and America and was music director, at various times, of the Vienna Court Opera, New York’s Metropolitan Opera, and the New York Philharmonic.

When the lower branches of an apple tree have been picked clean—as the symphonic form had been by Mahler’s time—one needs a tall ladder to reach the remaining fruit on top. The young composer found his ladder in two musical elements he knew he could take even further than his predecessors had: immensity and intensity.

Orchestras had already grown from about 50 players in Mozart’s time to 90-120 by Richard Wagner’s. The premiere of Mahler’s No. 8 required 170 players, solo singers, and three huge choirs, for a total of 1,030 performers. No wonder it’s called the “Symphony of a Thousand,” although a modern performance like Gustavo Dudamel’s Grammy-winning version scrapes by with a mere 350.

As if his mighty orchestra wasn’t enough, Mahler liked to add unusual instruments: a mandolin, a xylophone, even jangling cowbells and a hammer ominously pounding a block of wood in No. 6. He knew everything about orchestras, what each instrument and section could do and made brilliant use of them. His special effects included string players tapping their fiddles with their bows for a rat-a-tat sound, and placing horn players offstage to imitate music heard at a distance.

Mahler also super-sized the length of his symphonies. Most run 60 to 90 minutes, and No. 3 pops up in the Guinness Book of World Records as the longest in the standard repertoire.

The emotions get bigger, too. Mahler, in his music, wears his heart on his sleeve. He expresses and amplifies every human feeling, from delirious joy to deepest despair, and all the shades in between.

This intensity is what turns off some people to the composer. To them, his excitement is hysteria, his tenderness is saccharine, and his majestic climaxes are clichés. To such critics, the symphonies are drama queens: too long, too loud, a lot of sound and fury, signifying nothing.

Mahler suffered more than his share of personal tragedies. Eight of his 13 brothers and sisters grew ill and died in childhood. His beloved wife Alma was unfaithful, and their darling daughter Maria died of scarlet fever. No other composer probes grief and resignation so profoundly.

But he doesn’t leave listeners in the dark. His music leads us through life’s chaos and misery towards hope, meaning, and redemption. He turned his personal struggles into lasting beauty. All but one of his symphonies end in an uplifting major key. Even in his darkest moods, Mahler reaches for the light.

In 1907, Mahler met the Finnish composer Jean Sibelius, who told him a good symphony demonstrates “severity of form” and “profound logic.” “No!” Mahler exclaimed. “The symphony must be like the world. It must embrace everything!” He meant it. No composer is more eclectic. 

What did “everything” consist of? In his biography of the composer, Jonathan Carr writes: “Mahler once compared composing to playing with building blocks gathered in childhood.”

Mahler grew up in a small Moravian town called Iglau. The family lived upstairs in their house, with his father’s business downstairs: a tavern. Young Gustav probably heard country dance tunes called Ländler, and other popular music, drifting up from below. In childhood, he learned dozens of Czech folk songs and, from the age of 4, was able to play them on an accordion.

Troops were stationed at Iglau. Their military bands must have made a strong impression on the boy, since marches, trumpet calls, and fanfares recur in the symphonies. There are passages in the colossal No. 3 that might have been composed by John Philip Sousa.

Mahler’s family, German-speaking Jews, took him to the synagogue. He also sang in the choir at a Roman Catholic church. Later, as an adult, he converted to Catholicism.

You can hear all of these influences in the symphonies, along with Bach, Beethoven, and Mozart. The entire history of Western music flows through his works like a mighty river.

Although many composers use folk songs or popular tunes as source material, Mahler, even today, is criticized for incorporating “vulgar” melodies. Few tunes are more banal than the “Ode to Joy” in Beethoven’s Ninth symphony, but look what the composer did with it. Mahler, too, could turn a commonplace theme into musical magic.

Most of Mahler’s symphonies were poorly received at first. One critic wrote: “We shall always be pleased to see [Mahler] on the podium, so long as he is not conducting his own compositions.” Even after all the disappointments and bad reviews, the composer bravely told his wife: “My time will come.”

When Mahler died in 1911, a New York critic declared, “We cannot see how any of his music can long survive him.” There followed half a century of neglect. Academics and critics dismissed his symphonies as old-fashioned, bombastic, and overblown. Only a few conductors doggedly kept them alive, notably Bruno Walter and Otto Klemperer, who both started out as Mahler’s assistants. 

The modern Mahler revival was sparked by Leonard Bernstein’s revelatory recordings of the complete symphonies with the New York Philharmonic in the 1960s. There is no better place to start exploring these fascinating sound worlds. They’re all different, but all unmistakably Mahler. 

You might begin with his “Resurrection” (Symphony No. 2), which moves from a dark, disturbing funeral march to a joyous celebration of eternal life. In the finale, church bells ring as a choir exults: “Rise again, yes, you will rise again!” 

In 2010, the Guardian wrote: “A generation ago, you couldn’t escape cycles of symphonies by Beethoven, Brahms and Tchaikovsky. Now it’s Mahler’s … that orchestras most want to play, that conductors most want to conduct, and that audiences most want to hear.”

“My time will come,” Mahler predicted. Today it’s undeniable. His music is here to stay.