Miha Kosi’s research focuses on the medieval history of Central Europe, particularly the period between the 10th and 16th centuries. His topics centre on the Slovenian lands and their integration into a broader European context. As a historian and geographer, he adopts an interdisciplinary and comparative approach to the emergence and early development of towns, transport and trade routes, the formation of territories and borders, the role of political elites (especially the Counts of Celje), the Crusades and military orders, and historical‑geographical themes (historical atlases, historical topography).

Among his major scholarly achievements are the monographs Potujoči srednji vek on medieval transport in the Slovenian lands, Zgodnja zgodovina srednjeveških mest on the beginnings of urban development, and Spopad za prehode proti Jadranu in nastanek dežele Kras on the hitherto neglected political development of the Karst region in the 15th and 16th centuries. He is the author of the medieval chapter in the collective work Slovenski zgodovinski atlas (2011) and leads the project Historical Atlas of Ljubljana, which will present the city’s urban development from its beginnings to the present in line with international guidelines.

Through active involvement in ICHT and IHKEDO he builds international scholarly networks and promotes Slovenian research, including by organising two international conferences in Ljubljana in 2025 and 2026. His current and future work focuses on the Counts of Celje (the online portal Artistic Heritage of the Counts of Celje and an edition of their sources), on preparing historical atlases of Slovenian towns, and on studying medieval urbanisation in the wider Slovenian area.

• Špitali na Slovenskem v srednjem veku. V: KEBER, Katarina (ur.), BRATOŽ, Urška. Epidemije in zdravstvo : zgodovinski pogled, Miha Kosi. Založba ZRC, 2024.
• The history of Slovenia : the Middle Ages to the present. V: The geography of Slovenia : small but diverse. Miha Kosi, Miha Preinfalk, Petra Svoljšak. Cham: Springer Nature, cop. 2020.
• Potujoči srednji vek : cesta, popotnik in promet na Slovenskem med antiko in 16. stoletjem, Miha Kosi. 1998. Ljubljana: ZRC SAZU, Založba ZRC
• Zgodnja zgodovina srednjeveških mest na Slovenskem : primerjalna študija o neagrarnih naselbinskih središčih od zgodnjega srednjega veka do 13. stoletja
• Spopad za prehode proti Jadranu in nastanek "dežele Kras" : vojaška in politična zgodovina Krasa od 12. do 16. stoletja
• The Babenberg Dukes of Austria : crusaders "par excellence"
• Representative buildings of the Counts of Cilli : an expression of dynastic propaganda
• The Fifth Crusade and its aftermath : crusading in the southeast of the Holy Roman Empire in the first decades of the thirteenth century
• Ljubljana/Laibach in the southeast of the empire : the case of environmental relations of a Medieval city
• Das östliche transalpine Tor : Krain als "Transitland" im späten Mittelalter
• The beginnings of Medieval towns in the Slovenian lands and their "founders" : controversies and new interpretations
• Interaction between the city and its environment : the case of late Medieval Ljubljana
• Stadtgründung und Stadtwerdung : Probleme und Beispiele aus dem slowenischen Raum, Miha Kosi. 2009
• The age of the crusades in the South-East of the Empire : between the Alps and the Adriatic, Miha Kosi. 2001
• Die mittelalterlichen Städte Sloweniens im Lichte der Verkehrsverbindungen
• Gospodje Turjaški in plemiški svet na jugovzhodu cesarstva
• "Grbovna knjiga" gradu Turjak : umetnina kot odsev plemiške identitete
• Celjska klientela : socialna in prostorska mobilnost plemstva v službi grofov Celjskih
• Graffschaft Mettling : razvoj dežele in deželnega plemstva metliške grofije od 13. do konca 15. stoletja
• Sava kot prometna povezava Kranjske in hrvaških dežel v poznem srednjem in zgodnjem novem veku : (13.-18. stoletje)
• Zgodovina mest na Slovenskem - revizija in perspektive
• Križarske vojne
• Grajska politika - primer grofov Celjskih
• Dežela, ki je ni bilo : Posavinje med Kranjsko in Štajersko od 11. do 15. stoletja, Miha Kosi. 2008
• "Onstran gore, tostran Ogrske" : (Bela krajina v poznem srednjem veku), Miha Kosi. 2008
• Začetki mesta Slovenj Gradec : prispevek k nastanku mest na jugovzhodnem Koroškem v srednjem veku https://plus.si.cobiss.net/opac7/bib/28297005
• Morejska kronika in koroški vojvoda v bitki pri Pelagoniji leta 1259
• Cruciferi - Crucesignati : prispevek k zgodovini križarskih vojn in križarskih viteških redov v 12.-13. stoletju, Miha Kosi. 2005
• Predurbane ali zgodnjeurbane naselbine? : Civitas Pettouia, Carnium/Creina in druga centralna naselja neagrarnega značaja v zgodnjem srednjem veku. Del 1, Miha Kosi. 2005
• Freisinški škofje kot ustanovitelji meščanskih naselbin in začetki mesta Škofja Loka = Freisinger Bischöfe als Städtegründer und das Werden der Stadt Bischoflack, Miha Kosi. 2003
• --- quae terram nostram et Regnum Hungariae dividit --- : razvoj meje cesarstva na Dolenjskem v srednjem veku, Miha Kosi. 2002
• Templarji na Slovenskem : prispevek k reševanju nekaterih vprašanj srednjeveške zgodovine Prekmurja, Bele Krajine in Ljubljane, Miha Kosi. 1995. Ljubljana: Zveza zgodovinskih društev Slovenije

• The Art Heritage of the Counts of Cilli (October 1, 2022 - September 30, 2026)
• Slovenian Historic Towns Atlas (fundamental research project • July 1, 2018 - June 30, 2022)
• Slovenian Place Names in Time and Space (Historical Topography of Slovenia from the Middle Ages to the 19th Century) (fundamental research project • July 1, 2011 - June 30, 2014)
• Studies for the Synthesis of History of Slovene Towns in the Age of Feudalism (to 1848) (fundamental research project • July 1, 2004 - June 30, 2007)
• Artwork as Reflection of Knowledge and Networking. The Role of Education and Social Connectedness of Artists and Patrons in the Late Middle-Ages and Early-Modern Times (fundamental research project • July 1, 2018 - June 30, 2022)
• Man, Nature and Environment between the Northern Adriatic and the Eastern Alps in the Premodern Times (fundamental research project • July 1, 2011 - June 30, 2014)
• Basic research of Slovene cultural past 2015-2020 (research programme • January 1, 2015 - December 31, 2021)
• Soldiers from Slovenian territory on foreign soil in the past (fundamental research project • June 1, 2006 - May 31, 2008)
• Elenchus fontium historiae Slovenicae urbanae. – Edition of the Selected Sources for the Slovene Urban History. (fundamental research project • February 1, 2008 - January 30, 2011)

• Slovenian representative on the International Commission for the History of Towns (ICHT) since 2022.
• Member of the Atlas Working Group of the International Commission for the History of Towns since 2014.
• Slovenian representative on the Internationale Historische Kommission zur Erforschung des Deutschen Ordens (IHKEDO) since 2022.
• Member of the International Society for the Study of the Crusades and the Latin East (ISSCLE) since 2010.
• Member of the editorial board of the series Thesaurus memoriae.
• Member of the editorial board of the journal Kronika.
• Member of the editorial board of the series SHT – Slovenska historična topografija.