An introduction and conclusion are similar and important parts of any history essay. It is crucial though that you do not repeat yourself. An introduction directly addresses the essay question and clearly states how the essay will go about answering it and what it will be arguing in favour of. The examiner will then know exactly what to expect before reading the essay. Introductions are supposed to be short and concise, so you should not feel as though you need to write a full paragraph.
A conclusion serves to summarise the main points that have been made in the essay in more detail and to restate what you find to be the most convincing and accurate representation. You should not feel as though you need to make a bold, sweeping statement or introduce another point as this would make your essay seem less succinct and random. A good way to think about how to end an essay is to consider why the points you have made are significant.