Fhyujk

How would a Dictatorship make a country more successful (Wealthy, politically and materialistically powerful, secure, stable)?

Background:

In this instance the country is a monarchy to begin with. The provinces are controlled by different families who mostly do what they want... all of them have control over specific elements in the economy. Like the one family controls the Navy; another controls a large percentage of the country's produce; another controls the Banks. The Monarch is basically in place to give everyone a power check and keep the country united.

He is overthrown by the Family that happens to control the police force (but not the army, which is unprepared and not very large). The obvious answer for the benefit of a dictatorship is that the country is united behind one leader.

An important characteristic in this situation however, is that even after the change of power, the Families would still have some power...

Definition:

Dictator - a ruler with total power over a country, typically one who has obtained control by force.

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Note that this doesn't state that the Dictator is cruel or tyrannical. The common people actually aren't treated worse than before. The main difference is among the higher ups, like where the money goes and who has the final say in decision and international policy.

A well-run dictatorship is superior to any other form of government. Well-run dictatorships are unicorns though, since most of the goals I'm about to list are the exact opposite of what dictators are aiming for.

Why can a dictatorship be great? Because you can ignore special interests and other inefficiencies. You can remove corruption. You can invest heavily in the future without worrying about temporary setbacks. You can engage in long-term planning. You can make decisions quickly.

Special interests and other inefficiencies. You said that one Family controls the Navy, one the banks, one the produce, etc. That sounds like your entire nation is a series of monopolies, which is probably inefficient. Use your dictatorial powers to open up the field for competition. Allow the free market to improve productivity.

Remove corruption. Ruthlessly execute corrupt officials and strip their family of all assets. Make it so that the rewards of corruption aren't worth the risks, and you'll find your nation operating more efficiently at all levels. This one will actually affect the lives of normal people - imagine a medieval peasant actually being able to trust the police.

Invest heavily in the future, ignoring minor setbacks. Build those infrastructure projects. Educate your populace. Invite foreign investment and make sure that they have sustained legal protection so that even more flows in (no "nationalizing/stealing" foreign assets.) Use your stability and vision to forge economic alliances that boost your economy and open up markets for your corruption-free, open market industries to compete in. Fund research and exploration. Be prepared for war even when peace is long-lived.

You can make decisions quickly. In a democracy, even the most sensible decision can take time. The dictator can cut through red tape, can issue direct orders, and can bring the nation to action as fast as his commands can be distributed. An okay decision today is often better than a good decision a year from now.

The best example I have here is Pinochet from Chile. Pinochet was no angel - he killed/disappeared thousands of people (many of whom would be considered innocent). But the general consensus is that he managed to set Chile on a path that has made them the best nation in South American by almost any economic measure except equality. Even there, the modern Chilean poor are better off and less numerous than the Chilean poor when Pinochet took power, so judge carefully.

The intent of this answer is not to glorify evil in any way. I simply wish to state some truth. It is true that Adolf Hitler did many evil things and I don't want to make him sound good. but it is also true that Germany and its allies got terrifyingly close to taking over the eastern world. Only were they stopped by a coalition of the greatest forces in the world and some battles won barely dangling by a strand. This occurred because of the dictatorship of Hitler. I suggest to find more information about this look up things like "how was Hitler so successful?" or "why did Hitler accomplish so much?". I can provide more information myself I just do not have the time to do so at the moment but leave a comment if you would like me to expound upon this answer.

A common effect of political fragmentation is the imposition of economic barriers. Each subsection of the realm will institute trade barriers such as high tolls for transshipping goods, and possibly tariffs whose intent is to increase the prices of imported goods and make them less competitive with locally-produced products. The practice occurred, for instance, in many of the original American colonies.

This has a very bad long-term effect on the larger economy. Successful economies generally encourage specialization, with trade to distribute each specialized areas goods to the others.

It's entirely possible for a dictator to eliminate these barriers to the free flow of goods. This will have excellent consequences for the economy as a whole, although not necessarily for any particular realm.

Depending on the smarts of the dictator, it's also possible for him to institute (at least partially) a command economy, with resources devoted to projects with long-term payoffs which would otherwise not occur. An example might be investment in civil waterworks and piping, which will provide clean water to all, with an attendant drop in disease rates.

Of course, none of this is guaranteed to succeed. As the saying goes, "Power tends to corrupt, absolute power corrupts absolutely." This will apply to the dictator, and (importantly) to his advisors. Corruption in the application of otherwise well-intended projects can easily offset any benefits, and in the worst case produce a kleptocracy. This pattern is widely seen in third-world countries today.

In your specific case:

In your case, I think the new ruler is a new monarch, not a dictator. The new ruler doesn't have enough force or influence to rule with absolute power. Literally any of the other families could depose this new ruler in a heart beat. So I don't think they qualify as a dictator, unless one of the major families allies with them.

The problem is as follows:

Army beats Police Force.

Bankers + Money + Mercenary Army beats Police Force.

The specific scenario might make more sense if it was the army that took over and seized the whole nation. Or some group that can leverage extreme force.

In general:

That said, the ancient Greeks thought that a benevolent dictatorship would be one of the most ideal forms of government. They theorized many different ways to make this happen. But basically if you have a dictator who wants the good of their people, there are a lot of things they can do that traditional governments can't.

Income inequality, lack of jobs, civil rights abuses, almost anything can be solved with a hand wave and overwhelming force.

The problem is not having a benevolent dictator, the problem is that the people who tend to become dictators are not benevolent (usually traitors to begin with). And second, even if you get a benevolent dictator, as there have been in history, once they pass away their is no guarantee that the next person will be benevolent.