Most papers in economic history tend to be far less mathematical than other economic articles.  Many are also well written.  Here are a few things to keep in mind as you read the more challenging articles:

1.  First, read the paper's abstract, introduction, and conclusion.  These will tell you what question that the article is trying to answer, how the author tries to answer the question, and what the conclusions are.

2.  Second, re-read the paper's abstract, introduction, and conclusion.

3.  Notice the outline of the paper.  What is each section of the paper trying to accomplish?  Usually the introduction tells you what to expect in upcoming sections.  A common outline includes an introduction, a presentation of economic theory, a description of the data, the empirical results, and a conclusion.

4.  The figures and tables usually have something important to say (otherwise the author wouldn't have taken the time to separate them from the main text body).

5.  Skip over the more challenging parts of the paper during the first reading of the article.  Try to read the article through the first time without getting stuck in the details.

6.  Read the article a second (or third) time if needed.

7.  If the mathematical or statistical parts of the paper make no sense, try to understand what is being done, even if you can't understand how to do it.

8.  If you're really stuck, see Professor Eschker.

Also, this appendix on regression analysis may be helpful in understanding the statistical sections of a paper and this other appendix provides another example of regression.