There is considerable debate about whether programs should require the GRE, which can be prohibitively expensive for some applicants and may not say very much about an applicant’s abilities.

Do your research on whether the GRE is or is not required for admission to the programs you are most interested in.

If you take the GRE, study for it!  You want to do well on the analytical and verbal sections at least.  (Admissions committees in History programs usually ignore the math score). 

These can be expensive BUT many programs can waive those fees if you ask.

Don’t hesitate to ask—the worst someone can say is no and programs often regard application fees as a barrier.  Keep in mind that programs don’t set those fees—another element of the university bureaucracy does.

If you want to work on the history of a country other than the United States, you’ll need to possess language competence before you apply to graduate school because you’ll need to read primary sources in that language and (eventually) travel to it for research.

Some programs require non-Americanists to know two languages.

Use your undergraduate years to build your language capacity.  Students whose transcripts show that they are fluent (or nearly so) check an important box for an admissions committee.

Ask faculty who know you well and can speak at length regarding your abilities and interests.

Only ask academic faculty—your supervisor at the bank may know you well but is not in a place to discuss your academic qualifications.

Here you want to make the claim that you’re a good candidate for this particular program.

Avoid “I’ve always loved History” introductions; that’s assumed at this level.

Focus on the periods, themes, and questions that drive your passion for History—for example, “I’m interested in exploring the interplay of class and gender in industrializing European societies” or “I’d like to examine American foreign policy vis a vis Russia in the 1930s.”   Explain how your undergraduate training has prepared you to tackle this line of research.

The best writing samples are longer papers that integrate primary and secondary source research/analysis.

Your Senior Seminar paper is a natural fit for a writing sample but you may be able to use a shorter paper (e.g., 10-15 pags) as a writing sample.  Programs sometimes spell out their preferred length for a writing sample.