As Clara grew older, she didn’t know what to do. She found her occupation by working as a clerk in the Patent Office in Washington, D.C. She was one of the first women to work there. A few years later, the Civil War began, urging her to start working for the wounded after they were imported from the battlefields. Many died on their way to the hospitals that could be many miles away. She thought of a way to prevent this, and had the idea of nursing the wounded on the battlefields. She had a very hard time getting permission to travel on the battlefields, because the authorities felt that a war zone was not a place for a woman. Finally, in 1862, Clara received permission from a man named Officer Rucker. With her pass, she nursed the wounded at the Battle of Fredericksburg in December. Then, to her great sadness, her father fell ill. She went to her father's home and stayed by his side for a long time. The old captain told her that if she felt that she should take this risk, then she should do it. He told her to do what she thought was right. This gave her new courage, and after her father died, she went to the Battle of Antietam. She went on to become the superintendent of nurses for the Army of the James in 1864-1865. In 1865, Clara established an office to locate missing soldiers because she had gotten so many letters from worried and anxious families.  When Civil War ended, Clara was growing old. She was now turning 44. In 1870-1871, she worked with the Red Cross during the Franco-Prussian War and then helped organize military hospitals. Then, later in 1871, Clara also supervised the distribution of relief to the poor in Strasbourg, Germany. She tried many times to get the president of the United States to become part of the worldwide Red Cross. The president did not see the good cause in this decision and did not think it was worth it. However, Clara finally persuaded him to become part of the organization. She even started the American Red Cross in 1881, and she became its president. Red Cross aid was brought to the victims of the Johnstown Flood in Pennsylvania. During the same year, 1889, Clara organized relief efforts after the Flood. Then, the persevering woman went on to help people who were victims of the Spanish-American War in 1898. Two years later, she worked to relieve suffering caused by the hurricane at Galveston, Texas. After all of this exhausting work, Clara resigned from the Red Cross and went to live in Washington D.C. She founded the National First Aid Society in 1905. Her dream of helping others had now come true.