I decided to apply to Ph.D. programs, so my question is a bit moot! I did draft a SOP for a Ph.D. program, which did have a brief introduction about how studying abroad caused me to choose my field, before going into research interests, academic background, and preparation.
As for phrasing of my research interests, I wrote:
My intended field is modern European history, with a comparative geographical interest in Britain and Germany. I am particularly interested in historical and cultural memory and everyday life, with a special attention to the war, interwar, and post-war periods of the twentieth century. My intended research is a comparative study of daily life in Britain and Germany in the early to mid-twentieth century, with an emphasis on the effects of culture on nationalism and memory. Further, I would like to explore the intersections of gender, religion, and ethnicity in daily life during these periods. A side interest of mine is imperial conquest and its effects on culture and national identity.
I'm not sure if this is too broad, or if it is too abstract.