Please help me with this

Romanov: Expanded their empire mostly through military conquest, Royal family murdered in early- 20th century, Maria Theresa and Joseph I.

Both: Ruled over expansive and expanding empire, Formed after the Mongols were driven back.

Hapsburg: Expanded their empire mostly through marriage and political alliances, Had ruled over Holy Roman empire.

nothing certain is known about what happened, but it seems that the country declined gradually, perhaps due to bad government, or, more likely, due to a series of bad harvests, which resulted in widespread and recurrent famine.

i know social security wasn't one.

explanation:

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