A currency can descend from one account system, then adopt another currency’s unit or exchange anchor. Step-parent links make those choices visible.
12adopted-basis relationships
400currency identities
349ancestry relationships
0step-parents counted as ancestry
Purple connectors and recipient diamonds identify step-parents. They attach at the adoption or witnessed date, never back at the currency’s origin. Open the map with step-parents →
All twelve adopted bases remain unchanged. This regional pass does not promote daily market exchange or tax collection rates into hard pegs.
Tunisia adopted the French franc unit in the implemented 1891 reform while replacing local piastre accounting.
French franc unit adopted; no universal cash-conversion ratio asserted.
Mechanism: Officially reported unit substitution and franc-denominated issues.
The piastre remains the local succession parent. No continuing peg duration is inferred.
Evidence and exact locators
C1959 · supported
S465 — Collections: Protectorate monetary system Monnayage du Royaume de Tunisie sous le protectorat français, paragraphs 1–6 (web lines 241–247) Reopened and read the institutional account of the 1891 replacement of the piastre by the French monetary unit.
Relationship R0399 · Does not contribute ancestry or depth.
Hong Kong instituted a sterling anchor in 1935. Postwar tables document its continuation and 1967 parity change before the switch to USD.
Initially 16 HKD per GBP; 14.55 from 23 November 1967.
Mechanism: Exchange Fund and certificates backing banknote issue; postwar official parity regime.
Wartime operation and the exact pre-1972 break following sterling flotation are not fully resolved; do not read the outer dates as uninterrupted daily convertibility.
1967-11-23 — 14.55 HKD per GBP; revaluation within the sterling anchor.
The ECCA episode used a sterling peg before the EC dollar’s 1976 switch to USD.
4.80 XCD per GBP.
Mechanism: ECCA currency management with a stated sterling peg.
The reviewed start is the ECCA issue witness. Earlier British Caribbean sterling links remain to be scoped; this does not create a 1965 currency identity.
S1021 — Your Finances, Your Future — July 2009 Printed p.6; PDF index 5, The peg — 7 July 1976 Read switching date, both parities, reserve mechanism and cited Agreement articles 17(2), 24(2).
Relationship SP-V32-004 · Does not contribute ancestry or depth.
S1021 — Your Finances, Your Future — July 2009 Printed p.6; PDF index 5, The peg — 7 July 1976 Read switching date, both parities, reserve mechanism and cited Agreement articles 17(2), 24(2).
XOF acquired an explicit euro anchor from 1 January 1999 under the continuing monetary cooperation arrangements.
655.957 XOF per EUR.
Mechanism: Continuing monetary cooperation arrangements with an explicitly published euro parity.
The two CFA units remain distinct. The earlier French-franc anchor is retained in evidence and awaits a separately dated operational record. Ending and current operation are not assessed here.
XAF acquired an explicit euro anchor from 1 January 1999 under the continuing monetary cooperation arrangements.
655.957 XAF per EUR.
Mechanism: Continuing monetary cooperation arrangements with an explicitly published euro parity.
The two CFA units remain distinct. The earlier French-franc anchor is retained in evidence and awaits a separately dated operational record. Ending and current operation are not assessed here.
KMF acquired an explicit euro anchor from 1 January 1999 under the continuing monetary cooperation arrangements.
491.968 KMF per EUR.
Mechanism: Continuing monetary cooperation arrangements with an explicitly published euro parity.
The two CFA units remain distinct. The earlier French-franc anchor is retained in evidence and awaits a separately dated operational record. Ending and current operation are not assessed here.
Nader Shah’s implemented 1740 reform deliberately aligned Iranian rupee/naderi reckoning with Indian rupees and set one silver toman equal to 20 silver rupees. Record a qualified unit-adoption event, preserving Iranian ancestry; no continuing market peg is inferred.
1 Iranian silver toman = 20 silver rupees in the reform.
Mechanism: Accounting orders and replacement rupee/naderi issues explicitly aligned to the Indian rupee; supported by VOC and EIC reports reproduced in scholarship.
Qualified donor association and implementation scope. Commerce remained heavily copper-based. This is an adoption event, not a claim of enduring market parity or uniform compliance.
Relationship SP-V35-001 · Does not contribute ancestry or depth.
Admission rules
Deliberate, implemented adoption of another currency as a unit model or exchange-rate anchor, without replacing documented historical ancestry.
A named currency is deliberately selected; numerical coincidence is insufficient.
The rule governs the principal account unit or general monetary regime; limited sectoral scope must be explicit.
Implementation is evidenced by operative account definitions, conversion of obligations, issuance, redemption or intervention arrangements.
Evidence supports the precise subtype; initial equality does not prove a continuing peg.
Effective dates, observation dates, ratios, bands, mechanisms, endings and gaps are distinguished.
Subtype
Meaning
unit adoption
Dated adoption or redefinition of a principal account unit by explicit reference to another currency; no continuing peg inferred.
exchange rate anchor
Documented standing parity commitment with an operational monetary mechanism; dates, changes and limitations required.
False-positive exclusions
Shared metal content without explicit account-unit adoption
Coin design, mint technique, subdivision or name copying alone
Market exchange correlation or a quotation alone
A customs tariff or individual contract valuation alone
Reserve holdings alone
A proposal without implementation
Political conquest alone
Identity, kinship and time
Do not create a currency node for a peg, rescaling or change of monetary basis. A separately established new unit is adjudicated under the existing identity policy.
Keep founding ancestry. No transitive step-parent inheritance, sibling/cousin derivation, or automatic anchor succession. Co-anchoring requires overlapping evidenced periods and is not genealogical kinship.
Exclude every adopted-basis edge and its event dates from ancestry traversal, origin dates, predecessor coverage and all strict/qualified/optional depth metrics.
A unit adoption is an event. An anchor is a regime with dated observations and changes. Unknown end does not mean current. A switch closes the earlier anchor only where evidenced. Legal commitment and actual operation may differ.
Record a basket as a structured reference, never an invented currency or several unqualified bilateral parents. No basket is admitted in this revision.
Hard pegs and currency boards qualify when the specific commitment and implementation are established. A broad adjustable band, crawling rate, basket or observed market stability is recorded separately unless its precise arrangement meets these tests. A foreign currency replacing the local unit is still assessed under succession or absorption rules.
Retained revision32 context-link decisions
Held means the evidence needs a more precise unit, mechanism, implementation date or scope. It does not mean the historical relationship is disproved.
Sterling coin circulation and earlier ratings do not establish the operational sterling anchor for the scoped Belize unit. Inspect the later Belize peg legislation separately.
The 1904 US-gold legal-tender equivalence is preserved. Inspect the operative account definition and implementation before treating it as adopted-unit reference or sustained anchor.
Local peso conversion is established; retained evidence does not yet specify enough about deliberate USD-unit adoption or operational parity to assign a step-parent.
1903 gold-peso definition and US-gold tender rule are promising; commencement depended on coin supply. Resolve implementation before admitting a dated step-parent.
The named reference is the Ostmark, while the current endpoint is a broader German mark profile. Resolve the reference-unit mapping and implemented account definition.
French silver standard adoption alone does not establish adoption of the principal account unit under the new test. Inspect the Swiss enactment and account conversion.
Retained evidence concerns the French decimal silver standard. Inspect operative account-unit clauses rather than promoting metal or subdivision alignment.
The early 1825–1850 coin-rating record remains contextual. The separately evidenced 1965–1976 anchor episode does not retroactively validate this earlier interval.
A surviving rent with a peseta equivalent is an individual contractual valuation, not a general monetary adoption.
Further review
The retained evidence also contains 63 keyword-discovered claim candidates. These include duplicate observations, institutions and conversion evidence; their number is not a count of missing currencies or step-parents. Read the queue and access limitations →