Henry Thomas channels John Adams in ‘Sons of Liberty’

In “Sons of Liberty,” the three-part miniseries airing through Tuesday on the History Channel, Henry Thomas portrays John Adams, the serious Bostonian fated to become the first vice president and the second president of the fledgling United States of America.

In the series — especially in the early scenes — Adams is portrayed as something of a reluctant revolutionary, being a man of substance and a pillar of the Boston community.

Thomas, who did a fair amount of research before tackling the role, noted that when it comes to examining the lives of key American colonists in the late 18th Century, “it’s important to view them in the context of the times. … Even the most hard-core revolutionaries at the time — in their heart of hearts — considered themselves Englishmen, or at least part of that tradition.

“When it eventually came to establishing our own government, it was the English Bill of Rights that they were basing so much of it on.”

Reading things like David McCullough’s books, including his biography of John Adams and his “1776,” was very helpful for Thomas. Another source material that the actor found “invaluable” was “The Glorious Cause: The American Revolution, 1763-1789,” by Robert Middlekauff, mainly because what he called “a huge, thick tome of facts was great because it presents things from both the English perspective and the American perspective at the time. Middlekauff goes into a lot of what was going on in Parliament, plus the theories behind the major points that eventually made it into our own Constitution.”

As we chatted about the actual filming of “Sons of Liberty,” Thomas laughed when I asked where they made the series.

“It’s really funny. Here we were making a revolutionary war film set in Boston, so naturally we shot it in Bucharest, Romania!”

Such financial decisions happen all the time, but Thomas was quick to compliment the authenticity the miniseries’ production design team brought to the project. “To me, it all was very exciting. Yes, one of the reasons we shot in Romania was due to budget restrictions which prevented us from making it in the U.S. or England. But they built the most amazing sets. They re-created Boston Harbor on a backlot! In the more than 30 years that I’ve been acting, I can count on one hand the physical sets that are actually real enough that you can walk through and occupy and — in this case — squint a little and say, ‘Oh yeah! It looks just like 1776!’ It was an amazing thing to actually inhabit the sets and the great costumes they created for us as well.”

Thomas, 43, enjoys making period films and TV shows and has “done a fair share of them. Of course in this piece I didn’t get in on any of the exciting action stuff. I was kind of jealous of the guys who got to do a little musket firing and horseback riding and running around. As I get older I find I’m getting more into the elder statesmen roles,” quipped the actor who, of course, first came to our consciousness as Elliott, the engaging little boy in “E.T. the Extra-Terrestial.”

While Thomas said he “missed out on the swashbuckling” making “Sons of Liberty,” he still was delighted to be part of the History Channel project which he hopes “will get younger people excited and interested in the real history of the whole American Revolution — the idea of it and how this country was formed.

“Sure, it romanticized it a bit, but there are broad strokes that I think well convey the general feeling of change that was happening here in the late 18th Century.”

As for the how very establishment-oriented individuals like John Adams came to become leaders of the American Revolution, Thomas pointed out that had the British treated the colonists better, there might never have been a split with the mother country — or at least until much later in history.

“You have to remember that the Americans were always considered colonists, not matter what level of society they came from. You never would have upward mobility. There was no way, for example, a banker from Boston or a landowner in Virginia could go back to London and be treated like a lord of the realm. It simply was not going to happen.”

Of course, I couldn’t let Thomas get away without asking if he had watched “E.T.” with his own children.

“I have shown it to my kids. My youngest is 4, so it’s a little frightening for him. But my daughters have seen it and — fortunately! — they both really liked it.”