"The strong manly ones in life are those who understand the meaning of the word patience. Patience means restraining one's inclinations. There are seven emotions: joy, anger, anxiety, love, grief, fear, and hate, and if a man does not give way to these he can be called patient. I am not as strong as I might be, but I have long known and practiced patience. And if my descendants wish to be as I am, they must study patience." -Tokugawa Ieyasu
In the late 1400's, the ruling Ashikaga Shogunate of Japan became weak and lost its hold over the country. A many-sided civil war broke out, thus beginning the "Sengoku Period" - known as one of the most bloody and lawless periods in Japanese history, but also an era of some incredibly most heroic leadership.
Eventually, "Three Great Unifiers" came to power and ended the conflict through victory. These three were Oda Nobugana, Hideyoshi Toyotomi, and Tokugawa Ieyasu.
In the end, Tokugawa Ieyasu won, and his family ruled Japan for the next 250 years. However, he's probably the least popular of the three great unifiers in Japan.
Nobunaga is popular for having an incredibly fierce, martial, masculine spirit. At one point, the warrior-monks of the Honganji allied themselves against Nobunaga and harried, harassed, and ambushed his armies. The Honganji provided supplies, spies, and information for Nobunaga's enemies and sometimes faced them in direct combat.
When the Honganji would be losing, they'd retreat back to their fortress on Mount Hiei.
This was kind of a sacred place with many relics and many nuns and priests, in addition to the warrior monks. The monks would war Nobunaga on temporal authority, and then refuse to fight and claim amnesty under spiritual authority.
Nobunaga marched to Mount Hiei, and burned it to the ground.
I couldn't adequately explain what a shockingly big deal this is if you're unfamiliar with Japanese history. The closest example I could give be if an Italian Pope was opposing the French, and a French King had marched on Vatican City, burned it to the ground, and put all the high ranked members of the church to the sword.
Certainly, many rulers in European history would have wished to do something like this, but none of them did for fear of the very real repercussions and consequences.
But Nobunaga? No, he just did it.
Nobunaga was assassinated by one of his own generals in 1582. His oldest son had been groomed to take over for him, but also died at the same time. A power struggle broke out among his two highest ranking generals - Shibata Katsuie and Hideyoshi Toyotomi. Katsuie lost and was commit suicide in 1583, leaving Hideyoshi Toyotomi as the strongest man in Japan.
Hideyoshi went on to unify Japan, and is generally the most loved of the three great unifiers. He originally came from nothing, and worked his way up from carrying Nobunaga's sandals for him. Through his excellent use of diplomacy and martial skill, Hideyoshi was able to get promoted to foot-soldier, sergeant, captain, and eventually general. When Nobunaga died, Hideyoshi and Katsuie battled for command of Nobunaga's forces.
Hideyoshi won, and then kept winning. He conquered all of Japan.
He didn't stop.
He launched an overseas invasion against China and Korea.
Hideyoshi died of old age in Japan while his forces were fighting in Korea. They didn't hear of his death until nine months after he had died.
This caused a lot of ill will among his top generals, and let Tokugawa Ieyasu recruit many of them to his cause. Hideyoshi had died while his son was very young and had entrusted his top five generals to look after the boy until he was an adult.
Once again, the former Toyotomi forces split into two camps: Tokugawa Ieyasu's, and his opponent, Ishida Mitsunari.
At the Battle of Sekigahara, Ieyasu won, Mitsunari was executed, and the Tokugawa family went on to rule Japan for the next 250 years.
Tokugawa Ieyasu is generally not as well-respected as Nobunaga or Hideyoshi. Nobunaga was the ultimate masculine, ferocious warrior. When the religious authorities worked against him, he burned the entire religious capitol to the ground. In the first battle of his career - Okehazama - he was faced with overwhelming odds. Instead of fighting a defensive action, he snuck around to the back of the enemy camp, raided, and killed their commanding officer, thus sending the much larger force into disarray.
Hideyoshi is respected - he's the Japanese version of the American dream. This boy of no significant birth works his way from being a sandal-carrier, to a foot-soldier, to a sergeant, to an officer, to a general, to the ruler of all of Japan... he's known for being incredibly tactful, diplomatic, graceful, and intelligent.
Ieyasu has no such defining characteristics. Whereas Nobunaga might be represented by a blazing fire, and Hideyoshi might be represented by a beautiful butterfly - well, Ieyasu would probably be represented by a large boulder in the middle of a river. The boulder diverts things around itself, and the immensely powerful water must detour around it. But no ones looks at a boulder and says, "Ah! That! I will be like that!"
If you were being charitable, you could compare Ieyasu to an oak tree instead. Yet again, a powerful fire or a butterfly would be more inspiring than an oak tree to most people.
Yet, I respect Tokugawa Ieyasu the most. You see, Nobunaga and Hideyoshi both unmade themselves with their bad qualities. Nobunaga's ferocious temper is what led to his betrayal - in a fit of rage, Nobunaga had insulted and beaten the general who later betrayed and assassinated him.
Likewise, Hideyoshi's persistence and ambition led him to become the ruler of Japan, but then he was unable or unwilling to stop.
Without the fateful invasion into Korea, Hideyoshi's forces would have been de-mobilized and garrisoned after he had unified Japan, instead of mobilized and sent to war. A number of his top generals felt upset that they were fighting for Hideyoshi in Korea after Hideyoshi had already died, and no one told them.
This crack in their loyalty is what allowed Ieyasu to court them, and bring them over to his camp. I think it's fairly uncontroversial to say that without the Korean invasion, the Toyotomi dynasty is established to end Sengoku, instead of the Tokugawa.
Once again -
"The strong manly ones in life are those who understand the meaning of the word patience. Patience means restraining one's inclinations. There are seven emotions: joy, anger, anxiety, love, grief, fear, and hate, and if a man does not give way to these he can be called patient. I am not as strong as I might be, but I have long known and practiced patience. And if my descendants wish to be as I am, they must study patience." -Tokugawa Ieyasu
Indeed, I constantly search through my moods and emotions. Certainly, all of us feel joy, anger, anxiety, love, grief, fear, and hate from time to time. Ieyasu does not say to suppress or not feel those emotions.
Rather, he says to not give way to those emotions. I had a major professional triumph last week. I celebrated for six hours, and then got back to work.
You know, I'm scared sometimes of giving way to being joyful. It is a good thing to feel joyful, but not to let joy dull your edge. Likewise, consistency in action even if feeling anxious, consistency even if feeling fearful, consistency in love, consistency even if trapped in the thralls of hatred...
You can see that emotions unmade both Oda Nobunaga and Hideyoshi Toyotomi.
Ieyasu gave way to none of them. Certainly, he had his highs and lows. But his even, consistent temperament, in the best and worst of times, is what allowed him to build the most prosperous of all Japanese dynasties. Study patience.