Source: Playford (1653), Millar.
Interpreted by Douglas & Helen Kennedy in 1929
Setting: A longways set of as many as will couples.
Version: 1.0

   Up a double and back, two times. 
   The first couple casts off and lead down the outside, followed by everyone else, 
   back to place.

   Arched hey: All take hands, the first couple faces down, and goes under an arch 
   made by the second couple, then over the third couple, and so forth all the way 
   down and back, followed by all the other couples. When each couple reaches the 
   end they turn ar

  First couple turns by the right in the center, then by the left with the twos, 
  then by the right in the center, and so on down the entire line.

  Transcription (1653 Playford, provided by Dani Zweig):

  Lead up all a D. forward and back 3. times, cast off, meet below and come up, 
  do so 3. times: First Cu. go down under the 2. Cu. arms, the 3. come up under 
  the first, do this forward and back twice or thrice.

  First man set to the 2. Wo. then to his own, then to the 3. Wo. then to his own, 
  then to the 4. Wo. then to his own, and so to all the We. and men, then your Wo.
   do the same: then arm them as you set to them arming your Wo. then your Wo. as much.

  Lead up again, then turn your Wo. with your right hand, and the 2. with your left, 
  your Wo. falling as you turn, till you come to your place, then your Wo. do the same, 
  you following her, the rest doing these changes.

Video: https://www.youtube.com/watch?v=UWQVdr1UcRQ for 4 cpls Discussion:

A dance with this name is mentioned as early as 1551, but that mention is probably not the same dance. According to the Cunningham article on early references to ECD, the following item appears in a list of clothing: “Thre garmentes of sarsenett for them

The book “The British Broadside Ballad & Its Music” has a few references to Trenchmore:

Lodowick Barry's play Ram-Alley, act III, scene i: Justice Tutchin says: “Well I shall catch him in a narrow roome,/Where neither of vs can flinch; If I do,/Ile make him dance a trenchmoore to my sword.” The author lived from 1580 to 1629; I'm not sure ab

The Roxburge Ballads, volume XII, has a ballad, probably post-period, which is entitled “The West-Country Jigg: Or, A Trenchmore Galliard”. This might indicate that “Trenchmore” was a generic term for a vigorous dance.

The detailed set of steps we have comes from Playford in 1653, over 100 years later than the first mention. The steps given above correspond to how my local SCA group dances it. Playford repeats the first section 3 times instead of 2, the arched hey `twic

There is a similar dance named Chiaranzana in Il Ballarino, which dates from 1581. Miklos (andrew@bransle.ucs.mun.ca) is currently working on a reconstruction and translation. Negri also contains two longways dances.