Merge several vector datasets into a single one. More information: https://gdal.org/programs/ogrmerge.html.
ogrmerge.py -f GPKG -o path/to/output.gpkg path/to/input1.shp path/to/input2.shp ...
ogrmerge.py -f VRT -o path/to/output.vrt path/to/input1.geojson path/to/input2.geojson ...
ogrmerge.py -single -f GeoJSON -o path/to/output.geojson -src_layer_field_name country source_name path/to/input1.shp path/to/input2.shp ...