Question: What date was a battle fought on Bernards Heath

Context paragraphs:
Marshalswick: Marshalswick is an area of St Albans in Hertfordshire, England, located around 1.5 miles northeast of the city centre.  The whole area historically fell within the bounds of Sandridge civil parish, but it is now divided with the northern part in Sandridge and the southern part in the unparished area of St Albans.  Marshalswick borders on Jersey Farm, Fleetville and Bernards Heath.

Battle of Nibley Green: The Battle of Nibley Green was fought on 20 March 1469 (modern historians would date the battle in 1470 - prior to the adoption of the Gregorian calendar in England the start of the new year was 25 March; the battle being fought on 20 March meant it fell into the previous year), between the troops of Thomas Talbot, 2nd Viscount Lisle and William Berkeley, 2nd Baron Berkeley.  It is notable for being the last battle fought in England entirely between the private armies of feudal magnates.

Battle of Bealach nam Broig: The Battle of Bealach nam Broig (Scottish Gaelic: "Pass of the Brogue" ; also known as the Great Battle of Bealach nam Broig, Bealach nam Brog, Beallighne-Broig, and Bealach na Broige) was a battle fought between Scottish clans from the lands of north-west Ross, against north-eastern clans of Ross who supported the Earl of Ross.  The actual date of the battle is debated, it probably occurred in 1452 but the "Conflicts of the Clans" suggests a date as early as 1299.

Battle of Tsushima: The Battle of Tsushima (Russian: Цусимское сражение , "Tsusimskoye srazheniye"), also known as the Battle of Tsushima Strait and the Naval Battle of the Sea of Japan (Japanese: 日本海海戦, "Nihonkai-Kaisen") in Japan, was a major naval battle fought between Russia and Japan during the Russo-Japanese War.  It was naval history's only decisive sea battle fought by modern steel battleship fleets, and the first naval battle in which wireless telegraphy (radio) played a critically important role.  It has been characterized as the "dying echo of the old era – for the last time in the history of naval warfare, ships of the line of a beaten fleet surrendered on the high seas".

Second Battle of St Albans: The Second Battle of St Albans was a battle of the English Wars of the Roses, fought on 17 February 1461, at St Albans.  The army of the Yorkist faction under the Earl of Warwick attempted to bar the road to London north of the town.  The rival Lancastrian army used a wide outflanking manoeuvre to take Warwick by surprise, cut him off from London, and drive his army from the field.  The victors also released the feeble King Henry VI, who had been Warwick's prisoner, from his captivity.  However, they ultimately failed to take advantage of their victory.

Battle of Byeokjegwan: The Battle of Byeokjegwan (or Pyŏkje) (Chinese: 碧蹄館大戰; "Bì tí guǎn dàzhàn") was a battle fought on January 27, 1593 (January 26 according to the Japanese calendar of the time), between the armies of the Ming Dynasty led by Li Rusong, and the Japanese forces under Tachibana Muneshige, Ukita Hideie, and Kobayakawa Takakage.  As part of the Japanese Invasion of Korea (Imjin War), it was the first field battle fought during the war between the two sides.

Bernards Heath: Bernards Heath is a heathland in St. Albans, Hertfordshire, the site of the Second Battle of St Albans in 1461 during the Wars of the Roses.

Battle of Pima Butte: The Battle of Pima Butte, or the Battle of Maricopa Wells, was fought on September 1, 1857 at Pima Butte, Arizona near Maricopa Wells in the Sierra Estrella.  Yuma, Mohave, Apache and Yavapai warriors attacked a Maricopa village named Secate in one of the largest battles in Arizona's history.  It was also the last major battle fought by the Yumas and the last major battle fought solely between native Americans in North America.

Battle of Bloody Bay: The Battle of Bloody Bay, or Blàr Bàgh na Fala in Scottish Gaelic, was a naval battle fought near Tobermory, Scotland.  It was fought on the coast of Mull two miles north of Tobermory, between John MacDonald of Islay, the Lord of the Isles and chief of Clan Donald; and his son, Angus Og Macdonald.  The precise date of the battle varies in sources, from 1480 to 1483.  After the battle, in which Angus Og Macdonald emerged victorious, the latter seized power from his father, and held it for a decade.  However, Angus's victory would prove pyrrhic.  Many clansmen had died in the battle and nearly half the clan's fleet had been sunk, as a result of which the power of the Lords of the Isles was henceforth greatly diminished.  Angus, last of the independent Lords of the Isles, would himself be murdered ten years later, in 1490.

Battle of Glendale (Skye): The Battle of Glendale was a battle fought on the Inner Hebridean island of Skye, between the MacDonalds of Sleat and the MacDonalds of Clanranald, against the MacLeods of Harris and Dunvegan and the MacLeods of Lewis.  According to MacLeod tradition preserved in the early 19th century, the battle was fought in about the year 1490; yet it has been recently suggested that the battle more likely took place sometime after 1513.  MacLeod tradition records that the battle was the 'most tremendous battle' that the clan ever fought—although the clan was victorious, it never fully recovered from its severe losses.  MacLeod tradition relates how the MacDonalds originally had the upper hand during the conflict, but when the MacLeod's sacred Fairy Flag was unfurled the MacLeods gained heart and won the battle.

Supporting paragraphs: Bernards Heath Second Battle of St Albans
Answer: 17 February 1461