How should I structure a history essay?

A history essay should contain an introduction, around three sections containing your argument, and a conclusion. The introduction should be brief and should set out a basic answer to the question, and indicate the structure of your essay. Once the marker has finished reading your introduction they should have a clear idea of the structure of your essay and the themes you will be considering.
After writing the introduction to your essay, you should go on to your substantial arguments. It is a good idea to put your strongest or most important point first. That way, you can give reasons in the following sections for why the first factor was the most important in answering the question. Within each section, you should start by making a one-line statement of what your section will be about. For example, if you were writing an essay on the question of whether the marriage/succession issues affected Elizabethan domestic politics, you could write: 'The question of Elizabeth I's marriage and succession had a significant impact on domestic politics as it played a part in determining factional divisions in Elizabeth's Privy Council'. You would then go on to give evidence explaining the ways in which Privy Councillors were divided on the marriage/succession issue. This structure within sections is often referred to as P.E.E. ('point, evidence, explanation') or P.Q.A. ('point, quote, analysis').
Once you have dealt with the main points in your essay, you move on to the conclusion. The conclusion should not introduce any new information, but should sum up the essay, and tell the marker what your answer to the question posed is.