Great Britain (Volunteers)

100^th (Yeomanry) Regiment

	formed from HQ Royal Artillery, 44th Division/District (TA) and R (Surrey) Battery, 265th Light Air Defence Regiment, Royal Artillery (TA) │	formed from 257th (Sussex Yeomanry) Field Regiment, Royal Artillery (TA) │	formed from 286th (Hertfordshire and Bedfordshire Yeomanry) Field Regiment, Royal Artillery (TA) │	formed from 308th (Suffolk and Norfolk Yeomanry) Field Regiment, Royal Artillery (TA) │
	Creation of the Territorial and Army Volunteer Reserve
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1967:	HQ Battery,	200th (The Sussex Yeomanry) Battery,	201st (The Hertfordshire and Bedfordshire Yeomanry) Battery,	202nd (The Suffolk and Norfolk Yeomanry) Battery,
	100th (Eastern) Medium Regiment, Royal Artillery (Volunteers)
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1970:	100th Medium Regiment, Royal Artillery (Volunteers)
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1976:	100th (Yeomanry) Field Regiment, Royal Artillery (Volunteers)
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	Territorial Army
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1993:	│ │ │ │ │ │	to 127th (The Sussex Yeomanry) Field Squadron, 78th (Fortress) Engineer Regiment, Royal Engineers	│ │ │ │ │ │	│ │ │ │ │ │	from 307th (South Nottinghamshire Hussars Yeomanry (R.H.A.)) Battery, Royal Artillery
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	HQ Battery,		201st (The Hertfordshire and Bedfordshire Yeomanry) Battery,	202nd (The Suffolk and Norfolk Yeomanry) Battery,	307th (South Nottinghamshire Hussars Yeomanry (R.H.A.)) Battery,
	100th (Yeomanry) Regiment, Royal Artillery (Volunteers)
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1999:	265th Battery, 106th (Yeomanry) Regiment, Royal Artillery (V)	from 266th (Gloucestershire Volunteer Artillery) OP Battery, Royal Artillery (V) │	│ │ │ │ │ │	to 202nd (The Suffolk and Norfolk Yeomanry) Battery, 106th (Yeomanry) Regiment, Royal Artillery (V)	│ │ │ │ │ │
		266th (Gloucestershire Volunteer Artillery) Battery,	201st (The Hertfordshire and Bedfordshire Yeomanry) Battery,		307th (South Nottinghamshire Hussars Yeomanry (R.H.A.)) Battery,
		100th (Yeomanry) Regiment, Royal Artillery (V)
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		Army Reserve
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2020:		transferred to 104th Regiment, Royal Artillery	suspended animation		suspended animation

	Creation of the Territorial and Army Volunteer Reserve
	All TA Artillery specialist units and formations were grouped under a single unit. The new unit was formed as part of TAVR IIB.
1967:	Central Volunteer Headquarters, Royal Artillery
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	Territorial Army
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	Army Reserve
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2020:	221th (Wessex) Battery,	255th (Somerset Yeomanry) Battery,
	National Reserve Headquarters, Royal Artillery
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2023:	100th (Yeomanry) Regiment, Royal Artillery
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