Throughout history there have been many bad, mad, good and great leaders, these leaders may be military, political or religious and even evil.
Keep in mind that to be a great leader does not mean one has to be a great or even good person and some choices presented here are controversial.
Indeed being a good person is often detrimental to being a great leader and being a good person is not in many cases of leadership considered a desirable trait to have.
"Great men are almost always bad men"-Lord Acton
Charlemagne (742-814 AD)
Charlemagne was King of the Franks and Lombards as well as Emperor of the Holy Roman empire which comprised most of Christian Europe and while he was an impressive military commander, Charlemagne also known as Charles the Great makes this list not because of his unification of much of Europe or converting a large number of pagans to Christianity but rather because of his educational policies
Unlike many rulers at this time who couldn't read or write and believed that it was beneath them to do so Charlemagne made an effort to learn how and loved learning. In addition to learning himself Charlemagne encouraged everyone in his kingdom regardless of class to educate themselves.
Charlemagne loved getting and giving books as gifts and for the first time in history developed an institutionalised educational system allowing and encouraging all to learn rather than just those in the clergy. Charlemagne also had the clergy in his empire copy everything taken from areas Charlemagne had conquered into languages he and his people could read so that the educational process could continue rather than stop at what was known just in a select territory and developed a library system/repository for the books and scrolls during a time when it was more common for rulers to burn books rather than read them.
Because kings were warriors they seldom learned anything outside of warfare calling reading and writing the work of monks, Charlemagne not only made the effort to learn but required that his children, household nobles and staff must learn regardless of age at the time and gave the option of education to everyone else outside his household. Charlemagne opened public schools wanting all in the empire to become educated. This educational reform did not extend to just the males, females were invited to educate themselves as well and Charlemagne even scandalized his children's tutors when he insisted that his daughters were to be educated alongside his sons.
"Know this for certain, that unless you make up for your former sloth by vigorous study, you will never get any favor from Charles."-- To noble-born students whose work was poor compared to lesser-born children who had worked hard to learn to read and write well.
If he existed in today's society a man like Napoleon would be hard pressed to make anything of himself, however through sheer force of will, talent and blood letting he managed to conquer a sizable amount of Europe in the name of France.
Napoleon was a master at supporting and reassuring both his troops and the public which is what allowed him to continue raising troops for the Grande Army and keeping the support of the civilian population, if he had not had the ability to make his troops and public feel supported and confident they would not have put up with him as they did and it would not have been the British to finally defeat him as he would have been overthrown.
What makes Napoleon remembered and a great leader in our time is that people can learn from his successes, defeats and strategies. Napoleonic strategy is taught in many military academies throughout the world today and many businesses have business models based around Napoleonic strategies and examples.
"Great ambition is the passion of a great character. Those endowed with it may perform very good or very bad acts. All depends on the principles which direct them-Napoleon
Sir Winston Churchill (1874-1965)
Winston Churchill was undeniably one of the greatest leaders of the 20th century. Churchill led Britain through much of its darkest times during WWII by stepping up front to push his country into resisting the Nazi take over not just of his homeland but the world.
He was willing to make hard and even soul breaking decisions such as with the decision to leave Coventry undefended so that the Germans wouldn't know that the enigma code had been broken and unlike many leaders owned up to his mistakes.
In almost seven decades of service he made plenty of mistakes, owned up to them and made them right where he could and when it mattered the most stepped up to the plate admirably to lead the British through one of the darkest, deadliest periods of modern history.
"You have enemies? Good. That means you've stood up for something, sometime in your life." –Winston Churchill
Alexander the Great
While it is always possible to argue the "greatness" of a conqueror Alexander was undeniably a good leader as seen through his achievements and in the durability of his legacy. Alexander starting at the age of 19 built one of the largest empires in history all starting at a small backwater in Greece.
Alexander rarely lost a fight even against often incredible odds and was a builder on an incredible scale. Everywhere Alexander went he established cities, built roads, canal ways, harbors etc, and set up governments of local's rather than force his own people onto others when possible. This is not to say he wasn't a bloody, violent individual, Alexander liked to make examples of others in a big way and wasn't nice about it when he decided that step was needed.
However we view his methods Alexander achieved most of his goals and would have gone on to do much more if not for an early death.
All over the world today we can still see how Alexander has influenced all of history and still touches lives today. In modern times like Napoleon, Alexander is still upheld as a military icon and his strategies and history taught at military academies the world over.
"I am not afraid of a army of lions led by a sheep, I am afraid of an army of sheep led by a lion"-Alexander the Great
Qin Shi Huang Di
While undeniably an incredibly cruel tyrant to his own people never mind his enemies Qin Shi Huang was also a good leader during his (often bloody) reign that unified much of China.
In addition to being the driving force behind many incredible building projects, he also encouraged the advancement of art and developed a codified law system. As with all empire builders it is important to remember that one does not need to be a good person to be a good leader and Qin Shi Huang certainly exemplifies this, under his reign unknown millions died and much of the written history of the Chinese states was lost when he ordered the burning of all previous knowledge, the price for refusing to burn their scrolls/books or being found with a hoard of forbidden historical writings was always death.
"I have collected all the writings of the Empire and burnt those which were of no use."-Qin Shi Huang
Franklin Delano Roosevelt
FDR led the United States through both the Great Depression and most of WWII and was the only President to be elected to four terms in office. In spite of crippling injury due to polio Roosevelt created sweeping government reforms throughout his presidencies and like Churchill for the British led his people in the effort to keep the world free from Nazi rule.
Like any leader he made mistakes and unpopular decisions but he stepped up when he needed to and saw the country through several turbulent decades. One complaint about how he failed as a leader can be made about his acts as president were intended to help people immediately and were not necessarily beneficial to the future generations, something he himself was aware of and even pointed out himself when he made those decisions. A prime example being the social security system, a system that he knew would cause problems in the future but people needed the help now and as he stated he would be dead when it became a big issue.
The social security system was never intended to last as long as it has and while meant to help the citizens when it was created became a long term way for the government to defraud a nation. Many of the complaints that can be made about the longevity of FDR's programs/problems he passed because he knew he would not have to be the one to figure out another way or be around when the system he set up collapsed.
"The test of our progress is not whether we add more to the abundance of those who have much it is whether we provide enough for those who have little." -FDR
Martin Luther King Jr.
Martin Luther King Jr. was a non-violent revolutionary taken from the world far too soon. He was one of the greatest African-American leaders of the twentieth century who saw the United States and others across the globe that he inspired through times of strife created during the Civil Rights Movement.
While this movement and King's works were mainly here in the United states his works and words have inspired and guided generations the world over.
King was an incredible leader in his ability to inspire others to want and to demand equality, he inspired not only African-Americans but many Caucasians and Asian followers as well, which was one of his greatest accomplishments as he encouraged all people to work together.
Martin Luther King's courage and drive led and still leads others to stand up for a better world and life and our country is all the stronger for this incredible man's heart and mind.
"We must learn to live together as brothers or perish together as fools."- MLK
King Hammurabi of Babylon (1792-1750 BC)
Hammurabi turned a small city state into a great empire and he developed the Hammurabi Code (the first codified laws). Throughout his reign he improved areas such as navigation, irrigations, taxes and had numerous building projects to name a few.
His greatest failure was actually being too involved in the running of his government.
While he had many great achievements in life his empire did not thrive for long after his death because he had such a bad habit of micro-management.
"The first duty of the government is to protect the powerless from the powerfull"-King Hammurabi
Alfred The Great (849-899 AD)
Alfred is the only British monarch to have been given the title "great", one he well deserves for his development and defense of his country.
Alfred's best known act was the building of defensive fortifications and the defeat of the invading Dane's (Vikings) he however had many other accomplishments of note done for the benefit/betterment of his people.
Alfred established a unified code of law as well as encouraging his people to educate themselves, one of the few kings of England to ever do so.
Alfred believed that learning new things "makes life more rewarding and enjoyable". Alfred the Great also believed that "the worst thing of all is ignorance".
Adolf Hitler (1889-1945)
Unfortunately not all good leaders are good men, case in point Hitler. Technically while what he decided to do with his power, abilities and faith his people had in him was horrific and down right evil, the definition of a leader is not based just on acts but also on the ability to inspire and direct his people, toward his own goals which Hitler did in spades.
Prior to the start of WWII politically, financially and developmentally Hitler and his regime did more to build up the German people than the last several leaders before him combined and could have made Germany a world power on the same stage of power as Great Britain, the United States and Russia of today if he had not decided to try his hand at being a megalomaniac and created a Germany that is still in many ways trying to recover from the image created of it by the atrocities of WWII.
While in terms of actions he is evil personified, in terms of leadership he was one of the greatest leaders of the 20th century (No flames in the comments please, I know I will get objections to this but keep it polite, I am not in anyway saying I approve of, or support Hitler/the Nazi's, In fact i believe they are irredeemably evil but as I have stated many times throughout this article one does not have to be a good person to be a good leader.) Through his speeches Hitler was able to mesmerize and inspire his people, improve the economy and give them a positive self image, something they had not had since well before WWI.
Some Jews who attended his early speeches and have admitted to having been at them reported that despite Hitler's terrible message even they were moved by his presence and words and would have followed him if they had not been Jewish.
"How fortunate for governments that the people they administer to don't bother to think."-Hitler