<a href="https://en.wikipedia.org/wiki/Allan_Pinkerton" class="extiw" title="w:Allan Pinkerton">Allan Pinkerton</a>, President <a href="https://en.wikipedia.org/wiki/Abraham_Lincoln" class="extiw" title="w:Abraham Lincoln">Abraham Lincoln</a>, and Major General <a href="https://en.wikipedia.org/wiki/John_Alexander_McClernand" class="extiw" title="w:John Alexander McClernand">John Alexander McClernand</a>. Pinkerton was the head of Union Intelligence Services at the time. He also, allegedly, foiled an assassination attempt against Lincoln. His wartime work was critical in Pinkerton’s development, which he later used to pioneer the American private detective industry when he formed the <a href="https://en.wikipedia.org/wiki/Pinkerton_National_Detective_Agency" class="extiw" title="w:Pinkerton National Detective Agency">Pinkerton National Detective Agency</a>.
<bdi><a href="https://en.wikipedia.org/wiki/en:Alexander_Gardner_(photographer)" class="extiw" title="w:en:Alexander Gardner (photographer)"><span title="Scottish photographer (1821–1882)">Alexander Gardner</span></a>
</bdi>
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