A mass grave containing the remains of at least 3269 Napoleonic soldiers from 1812 was discovered in Vilnius, Lithuania in 2001. Stable carbon and nitrogen isotopic analyses were performed on collagen from 78 femoral samples to explore dietary variation within the sample. Starvation and nutritional distress were also evaluated through the examination of nitrogen enrichment in bone collagen. Clinical studies have demonstrated that enriched nitrogen isotope values can indicate periods of nutritional stress and starvation; however, this is the first study to examine its use as a diagnostic indicator of starvation in a historical population using bone tissue. According to the carbon isotope data, a vast majority of the soldiers in this sample consumed predominantly C3 plants with only five individuals consuming more than 50% of their plant dietary protein in the form of C4 plants, with δ13C ratios for this sample ranging from -19.22‰ to -11.76‰ and a mean of -17.18‰. This conforms to expectations given that a majority of human plant consumption in Europe is C3 pathway plants. Twenty-nine individuals exhibit enriched δ15N values, with δ15N values for this sample ranging from 7.14‰ to 13.63‰ and a mean of 10.49‰. The combination of historical and isotopic evidence suggests prolonged nutritional stress may be the cause of enrichment in this sample. The results of this study demonstrate the applicability of this method on archaeological samples as a line of evidence in the investigation of starvation and famine.