Sometimes, a topic for this essay forces itself on me. Other times, all topics seem to head out of town, leaving me with no inspiration. Then there are weeks like this, when a topic hides in the bushes and jumps out at me.

Sunday, after searching my brain all week, I was reminded that Monday would be St. Patrick’s Day, leading me thoughts of things Irish. The result is this column, which, I must warn you, contains absolutely no profound thoughts. That’s OK, though, because I’ve composed essays on serious topics the past couple of weeks, so it’s time for a little whimsy, and there’s nothing more whimsical than inspiration from a culture that features leprechauns.

Actually, writing about Ireland is an odd exercise for me. If there ever was an example of the great American melting pot, I am it. I’m just an American, and I have little interest in my ethnic background. I’ve never spent much time looking into it except in passing.

Moreover, my wife is only a little more into her Swedish background, which is why early in our relationship, she made sure I knew that Olson is spelled with an “on,” not an “en.” She has only a few Swedish artifacts around the house, such as a cookbook she never uses, a few plaques, and one poem about a horse and a girl identified as “Margareta, the fat and chubby.”

I also have a Swedish object, a textbook narrating the history of the U.S. through the Spanish-American War printed in Swedish. My mother-in-law gave it to me, possibly to integrate me into a family of Swedes.

It recalls a time when a Nebraska community with a population composed entirely of Swedish-speaking immigrants taught their school kids about American history in Swedish. I like it because it demonstrates that bilingual education is as American as apple pie, or maybe a Swedish meatball.

As for my actual ethnic ancestry, most of my genes hail from Germany by way of 18th and 19th century Russia or medieval England. Aside from several textbook anthologies of English literature, there isn’t anything in the house that recalls any of those three nations except a biography of Catherine the Great.

But while my family tree is primarily derived from such Teutonic souls, somewhere in my mother’s family tree, an Irishman sneaked in. I’ve never been clear on just when that happened, but Mom was pretty emphatic about his presence, and my best guess is that he accounts for approximately 5 ounces of my blood, give or take a couple.

This unknown Celt has had an outsized influence on my family, despite the fact that I never gave my ethnic background much thought, and I don’t remember my parents doing so either.

Still, my mom, whose red hair was likely a gift from that ancestor, loved Irish things, such the movie “Going My Way” and singer Bing Crosby, who won an Oscar for starring in it. As for my father, he too loved Irish songs, especially “The Rose of Tralee,” which was among his myriad favorite songs. He could also spend hours listening to recordings by the Irish tenor John McCormack.

Being good Baptists, though, they didn’t celebrate St. Patrick’s Day, although Mom at least took note of it sometimes, and she once helped me avoid middle school persecution by reminding me to wear green that day.

They also felt called to visit the Emerald Isle, but sadly, neither ever was able to do so.

I seem to have inherited their penchant for Irish music, although I’m attracted to earthier stuff than Irish eyes that are smiling or watching the sun go down by Galway Bay. That preference is itself kind of odd, because it seems most Irish songs revolve around three “w’s,” whiskey drinking, women chasing and warfare with the British or other occupants of a pub, none of which occupy my time.

Consequently when I hear myself humming about a jug of punch or the juice of the barley, I find it curious, since, although I’m not a total abstainer, I can certainly be classed as extremely moderate in imbibing. I was never successful in chasing women back when it was appropriate for me to do so, and I much prefer combat with the pen rather than the sword or my fists. Still, when I hear “The Rising of the Moon” or a somewhat bawdy tune called “Red-Haired Mary,” I’m apt to break into song.

My son seems to have picked up a smidgen of this Irish preference. When he decided to spend a semester overseas during his college days, he chose to spend it by Galway Bay. Whether hereditary or environment is responsible for that isn’t quite clear.

In short, I can’t really account for the outsized influence of this one ancestor. I just accept it as part of the mystery of life and enjoy the fact that it makes life interesting. I’ll continue to listen to the music, even though it’s at odds with my personality. I won’t, however, go out of my way to wear green, unless it’s just the right shade.

Someday, though I might run into a leprechaun, and I plan to ask him if he’s responsible for this Irish ghost in my genes, just to satisfy my curiosity.