1839. He chose to be jailed in Rochester to be closer to his family. He published The Caroline Almanack and drew an image of the Caroline affair for the cover. He also published issues of the Gazette, in which he described the trial and appealed for his release. Later issues reported on the upcoming New York state elections, the 1840 United States elections and the Durham Report. While imprisoned, Mackenzie's mother became sick. He was denied permission to see her, so John Montgomery, the tavern keeper of Montgomery's Inn during the Upper Canada Rebellion, arranged for him to be a witness at a trial. Montgomery convinced the state attorney to hold the trial in Mackenzie's house, and the magistrate stalled the proceedings so Mackenzie could visit his mother. She died a few days later, and Mackenzie witnessed the funeral procession from his prison window. Mackenzie encouraged friends and readers of his newspaper to petition President Martin Van Buren for a pardon, which would release him from imprisonment. Over 300,000 people signed petitions that were circulated in New York State, Michigan, and Ohio. Van Buren did not want others to believe he supported Mackenzie's actions and increase hostilities with Britain, so he was reluctant to grant this pardon. Democrats submitted petitions to the United States Congress calling for Mackenzie's release. Van Buren believed it was politically easier to release Mackenzie from prison than explain his imprisonment to fellow Democrats, so on May 10, 1840, Van Buren granted Mackenzie a pardon. After the pardon After a summer hiatus, the Gazette denounced all invasions into Canada and supported Van Buren's re-election. The paper's subscriptions continued to decline and the last issue was published on December 23, 1840. In April, he launched The Rochester Volunteer and printed articles criticising Canadian Tory legislators. The Volunteer stopped production in September 1841 because the newspaper was not profitable or politically influential. Mackenzie moved back to New York City in June 1842. Mackenzie worked for several publishers but refused to accept a job as an editor. He became an American citizen in April 1843. He wrote a biography of 500 Irish patriots entitled, The Sons of the Emerald Isle; the first volume was published on February 21, 1844. The goal of the series was to stop nativist attitudes towards immigrants to North America by reminding Americans that their ancestors were also immigrants. Mackenzie attended the founding meeting of