In July of 2015 two mummies were excavated from a site near Salekhard, Russia. The first mummy that was found was assumed to be a child or teenager from the 12th or 13th century. There have been discoveries at Zeleny Yar in the past that point to a medieval civilization which has yet to be fully understood.
At this location, 11 bodies have been discovered with missing or fractured skulls and bones, and 5 mummies were found shrouded in a copper 'cocoon'. The feet of the mummies at this site all were placed in a way where their feet were pointing towards the Gorny Poluy river, which has been known to have religious significance. One of the mummies dated back to 1282, however it is also believed that the others could be older.
These mummies are believed to have been accidentally mummified by a 'cocoon' containing copper mixed with environmental conditions.
While research is ongoing, to date only two apparent females have been unearthed from the site, one likely a prominent adult, now called the Polar Princess and one child with a copper mask.
Three other copper masked infant mummies - all males, were bound in several copper hoops, several centimetres wide.
Artifacts included bronze bowls originating in Persia, some 3,700 miles to the south-west, dating from the tenth or eleventh centuries. One of the burials dates to 1282, according to a study of tree rings, while others are believed to be older.
one of the adult mummies was found with an iron knife, silver medallion, and a bronze bird figurine. These are thought to date from the seventh to the ninth centuries.
Mummy of a child warrior from lost medieval civilization unearthed near Arctic By Anna Liesowska https://www.ancient-origins.net/news-history-archaeology/mummy-child-warrior-lost-medieval-civilization-unearthed-near-arctic-003445