The couple's romance also allowed both of them to rebel against powerful authority figures. Elizabeth's autocratic father complained that his only surviving daughter gave him more trouble than the rest of his children combined. And Napoleon, who was trying to secure his own hold on a throne, had no intention of marrying his youngest brother off to a commoner, regardless of how beautiful or rich she might be.

And if that weren't enough, Elizabeth and Jerome resembled each other so closely they could have been mistaken for brother and sister. Their marriage began to seem not merely desirable, but predestined.

"Elizabeth wrote a letter to her father," Deutsch says. "She said, 'Nature never intended me for obscurity.' "

After the couple exchanged vows on Christmas Eve 1803, Napoleon refused to allow his husband's new bride to set foot in France.

Napoleon asked the pope to annul the marriage. When the pope declined, the French ruler wrote to Thomas Jefferson and James Madison — who were then America's president and secretary of state, respectively — asking if there weren't something they could do to make this marriage go away. Jefferson also responded in the negative.

Napoleon contested the validity of the marriage and gave his younger brother an ultimatum: abandon his family and come back to France, or be left penniless and disinherited. Jerome caved and soon was married off to a German princess.

Napoleon eventually agreed to provide a $12,000 annual pension to Elizabeth for the education and upkeep of the couple's son, also named Jerome but called "Bo." But it was the rumor that the emperor planned to make her a duchess and her son a prince that really alarmed American society.

"Americans didn't know what to do with Elizabeth," Boyer Lewis says.

"We tend to forget how tenuous this republican experiment really was. We're all used to the United States being a success. But we could have failed. So a woman like her, a woman who orders a carriage with the imperial crest and flaunts her connections to the Bonapartes, made people really scared.

Moreover, Elizabeth made no secret of her disdain for republican — and even worse, democratic — forms of government. In response, Congress passed the so-called Titles of Nobility Amendment of 1810, which proposed to strip citizenship from any man or woman who received either a title or money "from any emperor, king, prince or foreign power."

Thomas Pickering, the former U.S. secretary of state, argued in favor of the amendment before the Massachusetts Legislature. According to Boyer Lewis, Pickering's notes for his speech reasoned that Elizabeth and her child were such a glamorous combination that they would "seduce Americans to these gorgeous scenes of royalty" and would cause members of the new nation to turn away from "this virtuous republic."

The amendment was sent to the states, and 12 states voted to ratify it — just one state short of the required three-quarters majority.

Elizabeth never gave up her dreams of securing a royal spouse for Bo or for his sons, Jerome and Charles. All three eventually married American women, which she counted as among the great defeats of her life.

"From an early age, Elizabeth kept a list of the princesses who she thought were eligible for Bo to marry," Deutsch says. "She really threw him at his cousin Charlotte, who was Joseph Bonaparte's daughter. Instead, he married Susan May Williams, an American railway heiress and a woman anyone would have wanted as a daughter-in-law.

"Elizabeth refused to give her consent, and said the most horrific things about that marriage. She really was the mother-in-law from hell."

A proud woman, Madame Bonaparte never stopped disparaging her homeland. She never stopped trying to leave America for good. But for reasons that remain unclear, she never succeeded

Four times, she crossed the Atlantic Ocean to Europe — at one point living abroad for several years. And four times she sailed back again.

In the last years of her life, Boyer Lewis says, she was spotted hobbling down the streets of Mount Vernon in her outmoded French fashions, personally collecting the rents she was owed on her 40 properties.

"Baltimore was still her home," Boyer Lewis says.

"She never really found a place in Europe. Her son was here and her grandsons were here. It was the place she knew best, and the place that knew her the best. Baltimore gossiped about her and denigrated her, but it also gave her status. We never stopped being captivated by her."

mary.mccauley@baltsun.com

If you go

"A Woman of Two Worlds: Elizabeth Patterson Bonaparte and Her Quest for an Imperial Legacy" runs through June 9, 2014 at the Maryland Historical Society, 201 W. Monument St. $6-$9. Call 410-685-3750 or go to http://www.mdhs.org.