George Creasey was born on February 24, 1818, in Newburyport, Massachusetts, to William and Hannah Creasey. He married Harriet Lewis in Newburyport on July 31, 1839, and they had at least seven children: George, born around 1840; Harriet, born around 1843; Sarah, born around 1845; Philip, born around 1847; Lewis, born around 1851; Emma, born around 1855; and Anna, born around 1858. They lived in Newburyport, and Creasey worked as a shoemaker. By 1860, he owned $900 of real estate. His wife Harriet died in 1860, and he married Hannah Ferguson on January 17, 1861. They had at least two children: Mary, born around 1862; and Hattie, born around 1866.
Creasey enlisted in the 8th Massachusetts Militia Infantry on April 17, 1861, and mustered in as a 1st lieutenant and adjutant on April 30. The regiment spent the next three months defending Washington. In May 1861, he rejoiced that “the Capitol is safe [and] the communication between the North and the South is opened.” Creasey mustered out on August 1, 1861. He returned to the Union army a year later, receiving a commission as a captain in Company I of the 30th Massachusetts Infantry on May 26, 1862. He mustered out on November 7, 1864.
He returned to Newburyport after leaving the army. By 1870, he was working as a Custom House clerk, and he owned $1,200 of real estate and $1,000 of personal property. A decade later, he was reportedly “out of employ.” He died in Newburyport on July 17, 1896.