One might suspect that a Philosophy of History might be somewhat niche in its focus. After all, when students learn about history, that typically happens during a class period called "History" and philosophy gets learned in "Philosophy," and so on. But actually, because of Hegel's intention, his Philosophy is comprehensive and complete in its scope. He hopes to summarize some basic principles that can explain not just why some people have said what they said about human history, but the actual nature of human history itself.
When he departs the directly related aspects of his lecture to take tangents on concepts like government theory, freedom, and the nature of human relationship, the reader might be tempted to say that it isn't really relevant to the main thesis, but again and again, he proves that such tangents are essential, because the flow of history is essentially a readjustment process where generation after generation takes turns suiting their world to their new developing opinions.
He views human history as the central aspect of the humanities, because by studying what humans have said, he gains a broad, portrait-like understanding of time and human nature, because the philosophies of mankind are a reflection of the human soul. This religious aspect is completely welcome in Hegel's discussion, and in fact, he even spends a considerable amount of time considering the human relationship to God, because the comprehensive aspect of his lectures are undeniably related to the "design of reality."