Genghis Khan was a blood-thirsty warrior who, according to some scholars, reduced the world’s population by as much as 40 million over two decades in the early 13th century. Along the way, his armies captured 12 million square miles of territory—the equivalent of the United States, Mexico, Central America, and South America combined.

Ruthless? Absolutely. And yet, what a great guy! To those close to him anyway. Turns out, Genghis Khan was quite the people person. You can learn a lot from him about making that sticky transition from ho-hum boss to inspirational leader at the office.

Bonus: The only things you’ll have to burn to the ground are a few bad habits.

Leadership Lesson #1: Don’t Just Know People—Know Their Why

Khan was a keen student of human nature, says Jack Weatherford, whose book Genghis Khan and the Making of the Modern World is often cited as the definitive history of the great warlord. He was curious about what motivated and satisfied people, and he was a firm believer in meritocracy and moderation to help his people coexist.

His greatest success, according to Weatherford, was unifying the unruly Mongol clans under one banner and then—after adding a bunch of other diverse cultures by annexing the many territories he conquered—establishing the largest, but one of the most peaceful, kingdoms in history.

Make It Work for You You’ll find plenty of warring factions at the office. The key to bringing them together is understanding their “why”—why do they come to work every day? To make a difference? Get away from the kids? Earn a paycheck? Once you tease that out, you’ll understand how to truly connect with and motivate them.

Leadership Lesson #2: Collect Your Enemies

A strong leader endears himself to others by appreciating their unique talents. Khan was famously loyal to his people, valuing such qualities as honesty, honor, and flair above all else.

While dissenters were brutally bumped off, appointments in the Khan’s army and government were based on skill, merit, and loyalty, with these traits generally overshadowing tribal bonds or even existing allegiances. When Khan recognized talent in his enemies, he often brought them into the fold. Many of his best generals and field commanders came from conquered nations.

This loyalty was rewarded with more loyalty. In Genghis Khan: Life, Death and Resurrection, British historian John Man notes that from his accession in 1206 until his death, not one of Khan’s generals betrayed him.

Make It Work for You “Keep your friends close and your enemies closer” isn’t just an overused Instragram meme. It’s the way great leaders build talented teams. Most leaders obsess about how to beat their rivals; the best ones focus on how to bring rivals aboard.

Leadership Lesson #3: Cultivate a Diversity of Ideas

Khan was always willing to listen to and learn new ideas, regardless of where they came from. In fact, though the Mongols killed most inhabitants of a defeated zone, they would often spare the lives of craftsmen, engineers, and anyone who knew how to read, write, or translate different languages.

The reason was twofold. First, Khan wanted to steal their best war tactics. But he also wanted to learn about their culture and society. He’s known for saying, “A leader can never be happy until his people are happy.”

Make It Work for You Are your people happy? If not, wipe that smile off your face and get to work.

Leadership Lesson #4: It’s Okay to Have Multiple Personalities

Khan allowed overthrown subjects to maintain their own cultures and traditions rather than forcing them into a Mongol mold. According to Weatherford, he even incorporated moral and spiritual lessons from other cultures and religions into the Yassa, the code of laws created to govern his people.

“People conquered on different sides of the lake should be ruled on different sides of the lake,” Khan famously said.

Make It Work for You Leadership isn’t a one-size-fits-all endeavor. Different people respond to different tactics; it’s your job as the leader to figure out how to manage each individual so that they can achieve their full potential.