Kenneth Lonergan is not the first name that comes to mind when you think “stately period piece.”

In a 25-year career as a screenwriter, director and dramatist, Lonergan has gravitated to contemporary tales of tragedy and alienation, often revolving around well-meaning, self-sabotaging screw-ups.

He clinched this reputation last year with a screenwriting Oscar for “Manchester by the Sea,” his wrenching portrait of an emotionally arrested Massachusetts janitor moving on — if not exactly recovering — from nearly unimaginable personal loss.

Lonergan also hadn’t worked in TV since penning two episodes of the Nickelodeon animated series “Doug” in the early 1990s, and had never adapted a novel. All of which made him an unlikely choice to write the screenplay for “Howards End,” a miniseries that premiered last weekend on Starz, adapted from E.M. Forster’s 1910 novel about the intersecting fortunes of three families in Edwardian London.

Even Lonergan wasn’t sure he was the person for the job. For starters, he’d never actually managed to finish the book.

“It just didn’t grab me the first time,” the writer said on a miserably rainy and windswept afternoon that felt like a scene from Forster’s novel, which turns on a misunderstanding involving an umbrella. “I don’t push through most books, which is not a good habit.”

He tried again and finished the book but worried about what he saw as Forster’s overly schematic exploration of class and its thinly developed romantic relationships, a point he raised with executive producer Colin Callender.

“My response was, ‘That’s exactly why we want you to write it,’ ” Callender said. He was excited by Lonergan’s portrayals of women and young people as well as his “peerless” range.

“I think what he does is explore character in great depth, and in a way that’s surprising and unexpected. He avoids the easy traps, the easy clichés.”

The result is a revelation: Lonergan has enhanced Forster’s novel rather than dramatically altering it.

The story follows Margaret and Helen Schlegel (Hayley Atwell and Philippa Coulthard, respectively), a pair of unmarried, upper-middle-class sisters, and their interactions with the wealthy Wilcox family, headed by Ruth (Julia Ormond) and Henry (Matthew Macfadyen), and Leonard Bast (Joseph Quinn), an impoverished insurance clerk with lofty cultural aspirations and a henpecking wife, Jacky (Rosalind Eleazar).

The four-part series offers a glimpse at a society in flux that’s historically faithful yet relatable to contemporary viewers, especially the independent, idealistic Schlegel sisters.

This version stands on its own merits despite the long shadow cast by the Oscar-winning 1992 film starring Anthony Hopkins and Emma Thompson. Lonergan said he wasn’t intimidated by the popularity of that adaptation, which he recalls only fleetingly. “I remember [two characters who] had sex in a boat, which struck me as unrealistic.”

The chance to work on a period piece was a selling point for Lonergan, who calls Stanley Kubrick’s 1975 “Barry Lyndon” one of his favorite films and cites the BBC’s 1995 version of “Pride and Prejudice” as “the gold standard of long-form literary adaptations.”