The study of invasive species is a critical area of research due to negative impacts on biodiversity and economies globally. The ecological impacts of invasive species have been the focus of a significant number of studies in recent years, however, less is known about how they adapt and spread in new environments. Stiltgrass (Microstegium vimineum) is an invasive species that was first discovered in the United States approximately 100 years ago near Knoxville, Tennessee.  Based on a previous study using digitized herbarium records, it is hypothesized that there were at least two introductions from genetically distinct source populations in Asia. However, few genomic studies across space and time for invasive species have been conducted, including stiltgrass. I hypothesize that multiple introductions have occurred leading to the genetic diversity present in the invasive range. Illumina sequencing via genome skimming was focused on plastomes, which are highly conserved in land plants and uniparentally inherited. They can therefore be used to track seed dispersal between the native and invasive ranges, and within the invasive range post-establishment. DNA was extracted from over 200 contemporary field collections and historical herbarium samples, and Illumina libraries were generated from all sampling locales collected and sequenced on an Illumina NextSeq2000. Plastomes were assembled with GetOrganelle and aligned with MAFFT, maximum likelihood trees were constructed using IQtree, and haplotype networks were drawn using PopArt. Plastome data were used to reconstruct the pattern of invasion history and specifically seed dispersal by using the uniparentally inherited plastome as a proxy for seed dispersal. Plastid genomic relationships were used to characterize geographic patterns of important traits (e.g. awn presence/absence) across space and time in the eastern USA and Asia and determine how genetic diversity differs from the native to invasive range. Constructed haplotype networks were used to trace the ancestry of individuals in the invasive range, using the native-range samples as a comparative reference for total plastome diversity. Historical samples are split into seven time slices of approximately fifteen years. Slices were studied to reconstruct the invasion history and track patterns of genetic diversity in the invasive range over time. All southern US accessions appeared to initially comprise the same haplotype, indicating a single introduction, possibly from Japan. Northern US accessions revealed multiple haplotypes that are most closely related to accessions in China, Japan, and Taiwan. Additionally, new haplotypes occurred over time, suggesting multiple introductions or a more diverse initial introduction than would be expected under a severe genetic bottleneck resulting from a single introduction. Furthermore, there is evidence for long distance seed dispersal as new haplotypes are found in increasingly large areas over time. Evidence for long distance seed dispersal and multiple introductions sheds light on a more complicated invasion history than previously thought, and illustrates how stiltgrass has spread since its initial discovery in the US over 100 years ago. The invasion pattern of stiltgrass can be used as a model to determine how other potentially invasive species might become established and spread to better contain and manage them.