Wisconsin native Mildred Harnack was the only American to help lead a Nazi-resistance group in Germany during World War II — and you've probably never heard of her.

Her largely unknown story is brought to light in "All the Frequent Troubles of Our Days" by Rebecca Donner, also the author of a novel, a graphic novel and many essays. But this book is personal — Mildred Harnack was her great-great-aunt.

"Three generations separate us. She preferred anonymity, so I will whisper her name: Mildred Harnack," she writes.

Donner relies on surviving family letters, declassified intelligence documents and interviews with survivors to tell Harnack's story. Photos and snippets of letters and papers are sprinkled throughout this compelling book, which reads like a tragic novel where we wish we didn't know the ending.

Harnack was guillotined on Feb. 16, 1943, at the age of 40 on Adolf Hitler's direct orders, which we learn on page 6. Yet knowing her terrible fate from the onset shouldn't dissuade you from reading this page-turner about Harnack's perilous journey, no matter how much you know about the Holocaust and the brave resistance movement.

Born in Milwaukee, Mildred Fish was studying for a master's degree at the University of Wisconsin when she met German doctoral student Arvid Harnack. The two married and she followed him to his homeland, where she taught American literary history at the University of Berlin. Mildred quickly became troubled by the rise of Nazism.

Donner's descriptive style takes us inside Nazi Germany and makes the book hard to put down. "Swastikas are cropping up like daisies everywhere: on posters pasted to the walls of U-Bahn stations, on flags and banners and pamphlets," she writes.

Mildred is most anxious about the politician gaining popularity, "a high-school dropout named Adolf Hitler who, Mildred predicts, will bring 'a great increase of misery and oppression.' "

She begins holding secret resistance meetings in her apartment, forming a group she and Arvid name The Circle. She recruits like-minded members who first distribute leaflets urging Germans to "resist, resist, resist," and later put their lives at risk feeding intelligence about Hitler's expansion plans to the U.S. and elsewhere.

We see Hitler's rise to power and increasingly violent crackdown on his perceived enemies through the eyes of Mildred and Arvid. Donner's book documents their sham trials on charges of treason. Its title stems from what a chaplain observed when he visited Mildred in prison, emaciated and struggling with tuberculosis, yet intensely focused on translating a volume of Goethe's poems into English.

"In all the frequent troubles of our days / A God gave compensation — more his praise / In looking sky- and heavenward as duty / In sunshine and in virtue and in beauty."

Mildred Harnack didn't survive to see the end of the war or Hitler's downfall. But her heroic actions may now get the attention they deserve through this heartbreaking work written by her descendant.

Laura McCallum is the politics and government editor at the Star Tribune. • 612-673-4781

All the Frequent Troubles of Our Days
By: Rebecca Donner.
Publisher: Little, Brown, 576 pages, $32.