The Gran Viejo de Nápoles, nick-named El Sangriento (‘The Bloody’), is probably the oldest of all Spanish tercios.
Its roots go back to the year 1509, when King Ferdinand V ‘The Catholic’ ordered the recruitment of a force of 5.000 men in Italy to protect Naples from the French.
Its first commander was Don Pedro de Zamudio, formerly a captain under Don Gonzalo Fernández de Córdoba during the second Italian campaign (1500-1504).
The first three tercios were formally established by the Imperial Ordinance of Genoa of 15 November 1536. The Tercio de Nápoles y Sicilia was one of them. It was later split into a Tercio de Nápoles and a Tercio de Sicilia. The title Tercio de Nápoles was first used in 1539 by Viceroy Don Ramón de Cardona of Naples. This tercio was divided into three coronelías of four companies each, totalling (on paper) 3.000 men.
According to Geoffrey Parker, the Tercio de Nápoles in 1571 had a strength of 2676 men, divided into 19 banderas, with the following arms distribution:
- 171 officers
- 281 musketeers
- 456 harquebusiers
- 962 coseletes (armoured pikemen)
- 806 piqueros (unarmoured pikemen)
In 1590, the transfer of command between Don Sancho Martínez de Leyva and Don Alonso de Idiáquez Gaspar caused irregularities and lapses of discipline resulting in the unit’s temporary dissolution. It was reestablished in 1591 under Maestre de campo Don Luis de Velasco, to be immediately dispatched to the religious wars in France.
The tercio acquired its nickname of El Sangriento or Tercio de la Sangre during the battle of Rocroi (1643).
For what it’s worth, here is the ensign I will use in my war games:
War in Italy (1511-1525): siege of Bastia
War in Germany (1544-1547): took part in the campaign of Carlos I in support of Hungary
War in Flanders (1557-1576): battles of San Quentin, Gravelines, Groningen and Gremmingen, occupation of Mons (Bergen) and Mechelen; siege of Haarlem, battle of Mookerheide, Worcum, capture of Antwerp (1585)
War with England (1588): part of the ill-fated Armada Invencible
French Religious War (1592): battle of Aumale, capture of Noyon and Calais
War in Flanders (1600-1604): Battle of Nieuwpoort (1600), attack on Oostende and relief of the town of Sluis
War in Germany (1614-1620): taking of Aachen, Düren and Wesel, occupation of Frankfurt and Worms
War in Flanders (1622-1634): capture of Juliers, Bergen-op-Zoom, siege and capture of Breda, battle of Nördlingen
War with France (1635-1693): battle of Thionville, occupation of Diest and Stevensweert, capture of La Chapelle, Chatelet, Corbie, Amiens and the fortresses of Emmerich and Berlaymont, capture of Menlau, Terremonde, Artois and Charlement; siege and capture of Lens, Aire, Landrecies, Armentiers; battle of Rocroi; capture of Mardijk, Lens, Landrecies and Dixmuide; siege of Gravelines and Dunkirk; capture of Rocroi, Arrás; battle of Dunkirk, Seneffe, Fleurus; battle of Neerwinden
War of Spanish Succession in Flanders (1703-1706): attack on Eeckeren, Capellen and defense of Brussels
War of Spanish Succession in Spain (1710-1715): defense of Balaguer, attack on Campomaior and conquest of Minorca
1715: Renamed and reformed by Royal Ordinance into Regimiento de Infanteria Soria Numéro 3