I'm going to have to disagree with the premise of this and the last post regarding history. History is fun, but not ultimately particularly useful. It's fun in that the "whys" provide narrative value to the facts of history, but as to why it isn't that useful, consider three points.
1. All history that you know is viewed through the lens of biased historians. Historians are extremely biased. All of them. Unlike the sciences where there is a reasonable control on bias (that is, experimentation and truth), in history there is no such control. The field becomes swept up in fads and memes and patterns, and looking at each one individually you would never know that it isn't just Truth. Since historians are the only ones who delve deep into the facts enough to have opinions, but there is no control on their opinions and biases, you essentially can't use any of their output for decision making today.
2. The devil is in the details. Almost always, the lines of implication and causality between two events that are connected (the "why") are extremely subject to minute details that are ultimately unknowable at this point in time. Identifying which of them are the true ones and which are only apparent is an exercise in futility, and creates a ripe environment for bias to exercise its magic (keep in mind that most humans are essentially rationalization engines, and are essentially blind to contrary evidence when faced with ambiguous data sets). The devil being in the details also means that any given scenario that you are faced with will differ very, very significantly from any prior scenario in thousands of details. History only operates at the level of the broad stroke, the gross events that have a literally incomprehensible number of details that could be important or not.
3. Lots of things happen due to chance. More things than people are willing to admit. Humans are wired to seek out patterns. Often this means humans find spurious patterns. Basing your decisions on things which are unknowably determined by random events is dumb.
I doubt if this will convince many of you, based on the responses these posts have generated, but at least keep in mind that your time is valuable, and learning the details of history may just not make your life one iota better.