You know that dramatic music everyone recognizes from The Nutcracker? The guy who wrote it was convinced it was mediocre. Pyotr Ilyich Tchaikovsky premiered his famous ballet in 1892, and he thought it was some of his worst work. History, thankfully, disagreed with him pretty spectacularly.

Tchaikovsky didn't start out destined for musical greatness. Born in 1840 in a small Russian mining town, he actually studied law and worked as a civil servant until he was 21. His father wanted him to have a stable career—which, fair enough, "composer" wasn't exactly a reliable income in 19th-century Russia. But when the Saint Petersburg Conservatory opened in 1862, Tchaikovsky quit his government job and dove into music full-time. His family thought he'd lost his mind.

Here's the thing about Tchaikovsky that makes him fascinating: he was brutally insecure about his work, yet he created some of the most confident, emotionally powerful music ever written. The 1812 Overture? Written in just six weeks because he needed money and didn't even like it much. Swan Lake? Initially considered a flop when it premiered in 1877. He struggled with depression throughout his life and had a disastrous marriage that lasted only weeks before his wife's instability and his own confusion about his sexuality made it impossible to continue.

But then there's his mysterious patron, Nadezhda von Meck. This wealthy widow supported Tchaikovsky financially for 13 years, giving him an annual allowance that let him compose freely. The twist? They agreed never to meet in person. They exchanged over 1,200 letters, discussing everything from philosophy to personal struggles, but maintained their strange arrangement. When she abruptly ended both the correspondence and the money in 1890, Tchaikovsky was devastated—not just financially, but emotionally.

Tchaikovsky died in 1893, just nine days after conducting the premiere of his Sixth Symphony, the "Pathétique." The official cause was cholera, though some historians suspect suicide. He'd told his brother the symphony was his most honest work, and it's heartbreakingly beautiful—dark and personal in ways his ballet scores never were. In the end, the man who doubted his own genius gave us the Romeo and Juliet Overture, Sleeping Beauty, and some of the most recognizable melodies in classical music. Not bad for someone who started his career as a clerk.