Fort Crawford Fort Crawford was an outpost of the United States Army located in Prairie du Chien , Wisconsin , during the 19th Century . The Second Fort Crawford Military Hospital was designated a U . S . National Historic Landmark in 1960 . The army ' s occupation of Prairie du Chien actually spanned the lifetime of two fortification s , both of them named Fort Crawford . The first of these was occupied from 1816 – 1832 , the second from 1832 - 1856 . Both of the forts formed part of a string of fortifications along the upper Mississippi River that also included Fort Snelling near Saint Anthony Falls in Minnesota , and Fort Armstrong in Rock Island , Illinois . Fort Crawford was also part of a string of forts built along the Fox - Wisconsin Waterway that included Fort Winnebago in Portage , Wisconsin and Fort Howard in Green Bay , Wisconsin . The First Fort Crawford . The U . S . Army ' s presence in Prairie du Chien began during the War of 1812 , when Fort Shelby was built on an island of the Mississippi River that formed part of the town . On July 19 , 1814 , Fort Shelby was captured by British forces and renamed Fort McKay . The British would continue to occupy Prairie du Chien until 1815 , after the Treaty of Ghent restored the pre - war border between the United States and British Canada . When the British retreated from the city , they burned Fort McKay rather than give it back to the Americans . To protect Prairie du Chien against future invasion , U . S . forces returned in June , 1816 , with orders to construct a new fort on the site of Fort McKay . This fort was named Fort Crawford in honor of William H . Crawford , the Secretary of War under James Madison . Built entirely of wood except for the magazine , the fort measured 343 ft on each side and included Blockhouse s at its northwest and southeast corners . Construction of the fort lasted through the summer of 1816 . Following the completion of Fort Crawford , the garrison was engaged primarily in peacekeeping between the new white settlers arriving in the region and Wisconsin ' s Native American tribes . Lieutenant Colonel Henry Leavenworth , a former U . S . Indian Agent , was among the early commanders at the fort . The United States conducted several negotiations with American Indians at Fort Crawford during the 1820s . One of the largest Indian councils in U . S . history was held at the fort in 1825 , when over 5000 representatives of nearly a dozen Native American nations gathered to discuss and sign the first Treaty of Prairie du Chien . Because of the first Fort Crawford ' s location alongside the Mississippi River , diseases such as malaria and dysentery were common among the troops , and the fort ' s wooden walls rotted because of the flooding that took place nearly every spring . The post took meteorological observations in 1822 . In 1826 , after a major flood , the garrison at Fort Crawford was ordered to leave Prairie du Chien and reinforce Fort Snelling in Minnesota . During 1827 , while no troops remained in Prairie du Chien , a group of hostile Winnebago Indians led by chief Red Bird murdered a family of settlers near the abandoned fort . This incident was the start of the Winnebago War of 1827 , and prompted return of soldiers to Prairie du Chien . Shortly after the troops returned , it was decided that the first Fort Crawford was no longer inhabitable . In 1828 a decision was made to build a new fort on higher ground . Maj . Stephen W . Kearny , commanding officer at the time , surveyed the area and chose a site for the new fort upon a hill near the Mississippi River ' s eastern bank . The Second Fort Crawford . The construction of the second Fort Crawford began in 1829 under the direction of the new commander , Col . Zachary Taylor , later President of the United States . The new fort ' s location on the mainland in Prairie du Chien was much more floodproof . In addition , to make the fort more weather - proof , it was decided to construct the structure using quarried limestone rather than wood . This in addition to delays in federal funding meant that the construction of the second Fort Crawford would take much longer than that of the first , lasting from 1829 until 1835 . Troops in Prairie du Chien were unable to fully occupy the new fort ' s barracks until 1832 , and in the meantime remained at the first Fort Crawford , where army surgeon Dr . William Beaumont did his best to keep the troops healthy . Beaumont would later achieve fame for a series of experiments on human digestion which he conducted at locations across the United States . Fifty - six of these experiments were conducted at Fort Crawford hospital , and allowed Beaumont to draw conclusions on the effects of temperature and emotion on the digestive process . As the second fort ' s barracks were being completed in 1832 , the Black Hawk War broke out in Illinois , and the troops at Fort Crawford were called to participate in the war . After the Battle of Bad Axe near present day Victory , Wisconsin , Chief Black Hawk surrendered to Col . Zachary Taylor at Fort Crawford . Black Hawk was imprisoned at the fort until he was escorted by Lt . Jefferson Davis to St . Louis , Missouri . Davis , who had been assigned to Fort Crawford in 1831 , would later become President of the Confederate States of America . It was while assigned to Fort Crawford that Davis met and fell in love with the daughter of Zachary Taylor , Sarah Knox Taylor . Colonel Taylor disapproved of the relationship between Davis and his daughter , and in 1834 Davis was reassigned to Fort Gibson in Oklahoma . Shortly afterwards , Davis resigned his commission in order to pursue his relationship with Sarah in Prairie du Chien . Upon discovering that Zachary Taylor would not consent to their marriage , the couple eloped to Kentucky , where Davis married Sarah Taylor in 1835 . During the 1840s the garrison at Fort Crawford was assigned to build a road between Fort Crawford and Fort Winnebago in Portage . The route they chose for the road is now followed by U . S . Highway 18 eastward from Prairie du Chien towards Madison , Wisconsin over Military Ridge , which is so named because of the military road which followed its crest . After the road was completed and the Winnebago Tribe was relocated from Wisconsin to Minnesota , the fort had little use . It was abandoned in 1849 . In 1855 Fort Crawford was reoccupied when rumors circulated of an impending uprising among the remaining Native Americans , but no such event occurred , perhaps because of the fort ' s reoccupation , and troops left the fort for the last time on June 9 , 1856 . Fort Crawford Museum . Except during the American Civil War , when the fort was used as both a recruitment center and hospital for Union soldiers , Fort Crawford was left unoccupied between 1856 and 1933 . In 1933 , the Daughters of the American Revolution began work on restoring a portion of the fort ' s hospital , while clearing away the remaining parts of the dilapidated fort to allow for development . The fort ' s hospital was then transformed into a museum of medical history called the Fort Crawford Museum of Medical Progress . This museum , which focused around the experiments of Dr . Beaumont , but also featured exhibits on other aspects of early medicine , was operated by the Wisconsin Medical Society until 1995 . In that year , the museum was sold to the Prairie du Chien Historical Society and converted into a museum of local history called the Prairie du Chien Museum at Fort Crawford . While the fort ' s hospital , which is registered as a National Historic Landmark , still houses exhibits primarily on Dr . Beaumont and early medicinal practices , adjacent buildings are now filled with exhibits on other aspects of Prairie du Chien history .