Answer:
There are different explanations for the same event in history because history is always written from the point of view of a person, or an institution, and this person, or this institution necessarily has a bias towards the causes and consequences of past events.
Step-by-step explanation:
For example, in the Renaissance, the Middle Ages were seen as dark period where art, science, and social development declined compared to the previous period: classical Greco-Roman antiquity.
The reason of this interpretation is that Renaissance intellectuals and historians were admirers of Ancient Greco-Roman culture, and despised the Middle Ages, since the Middle Ages brought an end to Classical Antiquity.
Centuries later, the Romantics, specially in Northern Europe, began to see the Middle Ages in a more positive light. The Romantics were not as obsessed with Classical culture, and they even despised some of the cultural elements of the Renaissance (excess rationalism for example).