In July 1842, he married Springfield resident Mary Ann Carey, before moving to Mexico City in November 1842. Bielaski spent eighteen months in Mexico, where he was employed as an engineer and declined an offer of Mexican citizenship made by Santa Anna. Returning to Illinois, he farmed for two years, but accepted an offer of employment with the General Land Office in 1845. Bielaski moved to Washington, D. C. for the position; by 1853, he had been promoted to a well-compensated position as a principal draftsman. After Lincoln was elected president, he would spend evenings sitting with Bielaski on the latter's porch. When the American Civil War began in 1861, Lincoln offered Bielaski a captain's commission to serve in the Union Army. Bielaski was initially reluctant to accept the offer because of his family, but was convinced to join the army by Lincoln. After joining the Union Army, he became an aide-de-camp for Brigadier General John A. McClernand. American Civil War While serving as an aide to McClernand, Bielaski was concerned about the armament of the Union troops. McClernand's men were largely armed with flintlock muskets retooled to use percussion caps. Bielaski felt that the Union cavalry should be armed with lances, as were French and Austrian armies as well as the Cossacks. Early in the war, the Confederate States Army controlled the towns of Columbus, Kentucky, and Belmont, Missouri on opposite sides of the Mississippi River, giving them control of the river. Union Brigadier General Ulysses S. Grant wanted to contain the Confederate positions, and boarded men onto transport vessels on November 6, 1861. After learning that the Confederates were planning an offensive, Grant ordered the transports to attack the Confederate camp in Belmont. A position near Belmont was reached on November 7, and the Union troops began moving to attack the Confederates, who were commanded by Brigiader General Gideon Pillow. While most of Grant's force encountered Pillow's Confederates, McClernand had detached the 27th Illinois Infantry Regiment, under the command of Colonel Napoleon Buford, to take a road to the Union right, and be in position on the other side of a slough from the main Union line. Bielaski accompanied Buford and the 27th Illinois Infantry during the movement. During the march, Buford learned that by abandoning his original directions and heading further down the road, he could strike the Confederates in the rear of their position. Buford decided